Gear Review – Garmin Fenix v Suunto Ambit

We’re extremely lucky here at Ultra168 to have the opportunity to test new gear, but the most frequent question we have been asked over the last 3 months is how does the new Garmin Fenix compare to the current market darling for performance GPS devices – the Suunto Ambit ?

In a nut shell it is a little like investing in property – the oft quoted “location, location, location” rings true with this review – the Garmin Fenix is like the best house on the worst street while the Suunto Ambit is the worst house on the best street. What does this all mean? Simply if you are going to drop $400 plus dollars on a watch right now, which is the best investment and will continue to deliver returns in the future?

To help put the review into context we will be judging the Fenix to the Ambit and more specifically looking at the two side-by-side in the fields of trail and ultra running. I understand that we often use our watches for other sports such as bike and hiking activities and each of the watches have strengths and weaknesses in these areas which we will making fleeting reference to.

So is the Fenix the big bad threat to the Ambit ? Here goes….

What you get:

Out of the box you get the watch, a charger, manual and the typical Garmin USB charger. Those of you who own the Garmin 610 will be familiar with the magnetised charger, the one for the Fenix is similar but has a built in clasp to hold in place. This is also used to download the data to your computer.

Weight and size are very similar to the Ambit – both of these watches are just small enough to wear everyday with a business suit or as a casual watch. Gone is the big bulky and quite frankly ugly look of the Garmin FR910 XT – a watch you wont find me wearing in a hurry now we have these new kids on the block.

The Fenix comes ready to go with the following activities :- Running, Sailing, Aviation, Fishing, Mountaineering, Cycling and Geocaching. You can add as many new profiles as you like to an endless list of activities. For example, during my time in Europe, I set up a specific activity called “UTMB” – this allowed me to only have some basic functions running over a maximum of 2 screens. I aimed to keep this simple as I was anticipating a 28-30 hour race. The same can be done with the Fenix – the one I had most fun with was creating a profile  for the activity of “Dogs” – my 2 Vizsla’s now have a number of PR’s on Garmin Connect to beat over the coming weeks !

Usefulness as a watch:

As an everyday watch the Fenix can be worn as a simple watch with a couple of neat features, the first is that it has a multiple timezone display – ideal for globe trotting ultra-runners. Secondly it adjusts the timezone you are in every time the GPS function is turned on. This is great if you fly to another city and head out for an early morning run, the watch corrects itself straight away.

The backlight has a number of customisable features. You can set it up to stay on for 15, 30 and 60 seconds, 2 minutes and constant. This ‘always-on’ feature is great for those who start out their training in the dark and want a constant display, eg paddlers and kayaker’s can now mount their Fenix at the bow and still see if clearly displayed. This obviously eats into battery life massively but is a useful feature for workouts. As a note, this is a recent firmware upgrade for the Ambit in the latest October release as well.

Battery Life:

Talking of battery life this is where I got very confused in coming up with a definitive number for its longest battery life. It claims that on 1 minute record feature you get 50 hours of battery life. The Ambit claims 60 hours. Both of these watches fall well short of this number when I left the watches running over the weekend. The Fenix reached 37 hours and the Ambit 48 hours respectively. The were left in the car and as we drove around the city of Sydney conducting chores and making short above ground trips, they both were pretty accurate in recording total time traveled and distance covered.

So is the 60 second record interval worth using ? For those who want to record a 35 hour endurance event then both watches will capture the basic data such as time and distance.

Where both these watches are likely to be used is in 1 second record mode with a number of additional features switched on like altitude, heart rate. In this mode the best I got out of the Fenix was 18 hours continuous use versus a remarkable 28 hours for the Ambit – way over the recommended lifespan for the battery.

So if you are looking to run a quality off road 100 miler like Western States 100 or UTMB or GNW100 – the Fenix offers about as much use in terms of battery life as the 310XT or 910XT. Even the Ambit would be a couple hours short for most middle of the pack runners.

Basic running features:

Going beyond battery life how does the Fenix step up as a running watch ? Well it has a wealth of functions to keep even the most analytical of athletes happy, but for runners it still falls short when compared to its Forerunner brethren. In its current release it doesn’t have two of my favourite Garmin 610 features – Virtual Pacer and Virtual Racer. Also it currently doesn’t allow the run/walk mode we are used to on older FR watches. And at present it is not possible to create an interval workout – for me this is a real pain. The latest from Garmin is that some of these features may be released in future upgrades – but when and if is always an unknown with Garmin. In defense of the shortfalls of the Ambit, Suunto have been ultra reliable in their communication about future upgrades and kept to those release dates.


Other features we come to expect from watches of this calibre include the ability to use as a way-finding device. The Fenix has a 3 D compass similar to the Ambit. The only problem is, I was unable to get it to calibrate easily. The Ambit asks you to rotate horizontally through 360 degrees clockwise and then tilt vertically through 90 degrees with a nice graphic that builds as you progress. The Fenix comes with no clear directions and so I was unable to get this feature to lock in. Pretty critical if you come to rely on this device as your only compass when on the trails.

The Fenix allows you to pre-load way points of a known course, and once you start your workout the basic display will let you know the distance and direction to the next way point. A neat feature is that it predicts your arrival time based on average moving pace. This is a great feature in ultras when working out nutrition and hydration strategies so that you crew know when to expect you.

You have a number of screens at you disposal to help with navigation, the outside of the display can act as a compass while other dates including maps can be displayed on the inside. This basic mapping feature was unavailable on the device I was using but who knows if Garmin will offer these maps as an upgrade/up sell down the road?

Both watches were remarkably close when it came to GPS accuracy. The Fenix was within 0.2kms of the Ambit over 10kms on my standard run around Centennial park in Sydney- although the cached GPS lock from the Ambit was almost instantaneous whereas the Fenix always took 30 seconds.

Other features:

Both the Fenix and Ambit come with a built-in Barometric Altimeter. Both watches allow you to manually calibrate as well as rely on basic GPS function to pinpoint altitude. This is where both watches seem to continually disappoint in terms of reliability of data. I live on Sydney Harbour and so it is fair to say if I dip my toes in the Pacific Ocean I am pretty darn close to sea-level. Yet when tested on bike rides over the last few weeks where I have ridden a number of 100km+ rides up and down some serious elevation gains and returned home to sea level I have had different totals from each watch and different final altitudes on returning home. How can this be? I am not sure which of the watches is more accurate for example when I leave the Ambit in its auto mode it frequently tells me I am -34m below sea level. At the same time the Fenix showed I was still 29m above sea level even though I was thigh deep in the water?

Both units have built-in external temperature recording options, but to be honest these were both as useful as a chocolate teapot. They are only useful as an indicative guide due to their proximity to your wrist and often underneath a waterproof jacket.

The Fenix comes compatible to the raft of ANT+ devices including Footpod, Pedal Powermeter and a new Tempe wireless temperature display unit.

One feature unique to the Fenix is the ability to pair with a smartphone (iPhone 4S or 5 and iPad 3 only at this stage). This is over their Bluetooth 4.0 technology, and also to share data to other Fenix users. I love this feature as you will be able to share fastest known times on routes and go out and follow them. Shame the virtual racer feature is not available yet to capitalise on this function.

The Fenix connects to your computer through its USB connector and the downloaded data is viewed through the tried and tested Garmin Connect. It is still as user friendly and analytically driven as for the other devices in the Garmin FR range. How does it compare to Suunto’s Movescount? That’s really a debate for another day as its like comparing apples with oranges in my view.

Living day-to-day with the Fenix I have one major observation which is quite frankly an ongoing frustration I have with Garmin watches – that is the quality of the hardware and the reliability of the device. On at least 5 occasions the device froze when I was trying to customise fields and the unreliability of pairing with my HR belt proved to be a little exasperating on the rare occasions I wanted to use the belt. A final thought on build quality – the Fenix just doesn’t quite feel as solid as the Ambit – not sure what it is, but it just has a cheap feel to it. It is a superficial thing I know , but the Made (and assembled) in Finland logo on the back of the Ambit makes me feel reassured. Having had 2 FR610 returned to Garmin on the last 12 months – I hope the same cannot be said of the Fenix. Garmin will have to work hard to be truly trusted by the outdoor adventurer heading into the wilderness for several days relying on this as their sole navigation device.

Summary and verdict:

So in summary, the Fenix has a heap of features, many I will never get close to using on a daily basis as an ultra-runner, but at the same time the shine is dimmed somewhat by reliability and build quality. The Ambit feels like it has more features to come to match the Fenix but has the right foundations for regular upgrades in the coming weeks and years. As your Real Estate agent would advise – buy the worst house on the best street and look to upgrade. The Ambit fits this mould. The Fenix is in the alternate camp – packed full of features but stuck in the wrong location. A nagging thought is that Garmin rushed the Fenix to market to keep within sight of Suunto as the Ambit sat without any major competition in the serious explorer and ultra-runner space for several months potentially grabbing large chunks of the market.

For now I will be sticking with my trusty Ambit and looking forward to its new firmware upgrade in November (ANT+) all the while hoping secretly that Garmin fix their teething problems and roll out consistent and reliable upgrades as and when they are fully tested.


Garmin Fenix  4/5

Suunto Ambit 4.5/5

*Declaration – Garmin Fenix was loaned to me from a fellow ultra-runner with no commercial ties to Garmin. The Ambit was provided to me to test courtesy of Footpoint Shoe Clinic, a provider of both Suunto and Garmin watches.

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35 thoughts on “Gear Review – Garmin Fenix v Suunto Ambit

  1. Marcus, re: altimeter readings, to calculate elevation GPS receivers use a theoretical sea level estimated by a (WGS84) ellipsoid, which does not perfectly follow the theoretical Mean Sea Level, so what to you may be sea level may not be if acquired via GPS. If no location reference points (within 15mtrs) are saved on the fenix with a known elevation reference, then altitude is derived from the ellipsoid from GPS. One nice feature of the fenix is that you can display both barametric and GPS derived altitude on the one screen, I use this along with the GPS accuracy metric on the one screen. To Garmin users, always save a starting point location with a known elevation reference. The Ambit at the moment calculates elevation based on pressure only, so relies on accurate reference values to be set. If the air pressure changes whilst you are in altimeter mode climbing and descending then the altitude can be out, especially over a period of time like a longer bike ride or ultra. Adjusting the reference value during the activity from say a trig point can help maintain accuracy. Hope that helps a little. chilli

  2. that’s a really helpful comparison. I guess that one question is: How can Garmin keep ahead of a unit that’s designed to be constantly evolving? The two main features I have always liked in the Forerunner series over Suunto’s Ambit are the breadcrumbs trackback feature, which I think has now been matched, and the customisable-on-the-run feature, which I think still stands as a point of difference.
    Has Suunto yet said whether they will look at an update in future releases that would allow screen customisation on the go? With the same number of buttons, the Fenix screens can be changed at any time. I don’t know whether that’s a software or hardware-dependent issue, but it would certainly be nice to not have to modify Ambit readouts via computer.

  3. Great review, thanks- have been waiting for a comparison! One question, can either watch be charged while in use via a Powermonkey or similar….? Thanks

  4. IMHO the ultimate ultra gps is the e-trex series.
    It’s not even a watch, it’s a handheld. but for a 100 milers it’s ideal since it uses replaceable AA batteries that last 25 hours.
    It has full off-road vector maps (easily downloadable on the internet for free) and you can actually use it to navigate while in the trail.

    The one obvious disadvantage – it’s not worn as a watch but I actually think it’s not heavier than, say, the 910xt (Just by feel).

  5. There’s a really good discussion forum about the Ambit/Fenix comparisons on WatchUSeek Suunto forum

    I’ve had an Ambit since April and I really like it, but there are some issues I’ve found, e.g. the calorie count for an exercise on the watch is different to the calorie count shown in Movescount. It had been up to 50% lower on the watch until the recent firmware update. It’s now up to 20% lower. Suunto’s not very response to these types of issues unfortunately.

    Still, I’ve used it for fell running in the clouds in the UK in bad weather and for ultras here and it’s been great. For Oxfam this year, I put it on 60s GPS fix as we planned 18 hours, and the route distance then came in at about 90km, so a good 10% down on the official 101.5km.

  6. Are you sure that “The Fenix comes compatible to the raft of ANT+ devices including Footpod…”?
    I have a fenix and a footpod from the FR60, and as of firmware v2.8, the fenix still only seems to be compatible with the bike sensor and Tempe, not the footpod 🙁

  7. What a thorough and insightful review!
    I would love to see what you make of Misfit Wearables’s debut.
    We are doing something very cool: an all metal waterproof tracker that can cope with running, bikes and swimming. It is totally wireless: (no buttons, no cables, no Bluetooth pairing, no charging docks).
    We’ll be back soon with more news. In the meantime, watch out for Misfit Wearables!

  8. Good day,

    Wondering if you can help me here, I’m looking for a wrist watch, GPS that I could navigate me to way points and free dive the marks, whether it be a reef or wrecks.
    This would mean taking marks, or way points and being able to swim to a specific spot.
    Which device would you reccommend?
    Much appreciated.
    Great review.

  9. My thinking around Garmin is coloured by my recent experience of them as a company. I use a GPSMap62. Which is a great unit. However the compatibility with Connect was removed and I was told I needed to use Basecamp. Which is totally unsuitable and not much use unless you spend another £100 on maps. When I brought this up I got what amounted to an FU e-mail from Garmin. My son has an Ambit and now that I have read this it has reinforced my opinion that in the absence of being able to use Connect with my GPSMap I’m not forking out for a Garmin but will be investing in the Ambit.

    1. There have been various discussions about this on the watchuseek forum

      With the Ambit 2, it’s possible to switch exercise mid way, so you can have a 1s GPS recording interval and then switch to a 60s one to conserve battery and log space.

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