Gear Test: The battle of the Merino tops

As Australia, and indeed the Southern Hemisphere moves out of our so-called ‘winter’ and into summer, the past few months have given me the opportunity to test some colder climate gear for those times where we dip dangerously into single figures celsius 🙂 Nevertheless, it can get pretty cold over here at times, which is when I tend to look for something more than just a singlet, that we’re so blessed to be able to wear most of the time we run down here in our little back water.

You might be asking why we’re doing a review of what you might regard as colder climate gear as we head into the summer months? Well, regardless of colder climes or not, many manufacturers of the merino will have you know that the stuff is not just for winter, but can be worn in the summer too. Now I’d probably draw the line at anything hitting 30 degrees and above, but it’s surprising what you can get away with in the warmer temperatures with this stuff. We also have to remember that while we, the lucky ones in the Southern Hemisphere celebrate Christmas day baking in the heat and whacking a shrimp on the BBQ, there’s a whole bunch of people up in the Northern Hemisphere betting on what time between 3-4pm it’s going to get dark and hitting minus 10 or below.

A 'Kiwi' man looking for sheep
A ‘Kiwi’ man looking for sheep

For this little test, which spanned around three months or so, we got our hands on three items of merino-based tops from three different manufacturers around the world. Typically, when you think merino wool, you think of Kiwis. They like sheep, some more so than others, but there’s a fondness that Kiwis seem to have with our four-legged friends.

Our first bit of gear comes from a brand that a lot of your will know, Icebreaker. Next up, we’ll have a local Aussie-based supplier by the name of I/O Merino, then lastly the Japanese sounding, English based company, Ashmei.

Confused? So am I!

While there are many different types and weights of merino you can buy, we generally went with the lightweight versions of these brands, as that’s what runners tend to use, unless you’re embarking upon the Antarctic marathon at some point.

Before we get into the nitty-gritty of the ‘test’, I will add this. To the average person, merino is merino. You’ve really got to be a merino nerd or connoisseur to understand the nuances of different sheep like threads, and if we’re honest, most runners don’t care about that. We just want to know a few basic things, such as:

  • Is it comfortable?
  • Is it practical?
  • What’s it like it different conditions? Wet/Dry
  • How much does it cost?

And this is what we’ll be basing our review on today. We’ll also add that we didn’t test like for like products as we thought that would be too boring. So while we can’t make direct comparisons to some of the practicalities of how and where the top can be used, we’ve tried to place each in context, knowing that direct comparisons in some areas is unfair.

First up, its our sheep-loving friends over in the Eastern Island of Australia, the Kiwis.


The Icebreaker Crewe
The Icebreaker Crewe (pic: Icebreaker)

As mentioned above, this is probably one of the most popular brands on the market indeed in Australia as it is in New Zealand. A brand that’s been around for a while, and if you were to describe it, one you trust. It seems to appear on the kit lists of most races, well certainly the ones I’ve been too. But how did it fare in our testing?

  • Is it comfortable? To be honest, when you first put it on, no. I do find a certain level of ‘itchiness’ whenever I’ve put an Icebreaker on. It only lasts for an hour or so, and it’s not extreme to say the least, perhaps moreso about the body getting used to the fabric. But generally once it’s on, you’re fine. The fit of these is pretty good too. I have quite a long torso and find that the Icebreaker is long in the torso. 7/10
  • Is it practical? For the most part yes, but the top I tested (long sleeve crewe) didn’t have a collar, pockets or extra bits that enable you to cover half your hand. I see since I purchased this, there appears to be a lot of these extra bits or versions out now to rival the likes of Ashmei. Although I can’t speak with authority on how those would fair, it’s safe to say that the top I used is probably better used as one of those ‘unused’ pieces of gear most races make you carry and stuffed at the bottom of your pack. 6/10
  • What’s it like in different conditions? I think this is where the Icebreaker excels a little bit over the other two. I’ve found that when it gets wet, either through rain or vast amounts of sweat, it tends to dry a bit quicker and doesn’t feel so ‘clammy’. If we’re honest, most wet merino is a bit like jumping into a swimming pool with a pair of jeans on… it’s that kind of yucky feeling. But the Icebreaker is the least ‘yucky’ of the three when it comes to the varying levels of ‘clammyness’. 8/10
  • How much does it cost? The Icebreaker (my version), is the mid-range coming in at a cool $89.95 kangaroo dollars, or around $115 sheep dollars, which is what I paid in the Icebreaker store in Queenstown, NZ. That would be around fifty of your hard-earned English golden nuggets.
  • What’s it best for? This particular top is one of those bog standard tops that you might need for races, but will probably wear just a few times a year. It does the job for sure, but if you’re going to use merino on most of your runs, you’d probably want to consider something with a bit more practical use.
  • Total score: 21/30
The altitude zip base layer from I/O
The altitude zip base layer from I/O (pic: I/O Merino)

I/O Merino

Now it’s the turn of the Aussie battler, I/O Merino. Now, the claim to fame with these guys is that they say they’ve been working with wool since sheep were invented. A joke of course, but they do have six generations of wool-making history in the family, despite I/O being a relatively new company. What’s their point of difference? Well it comes down to quality and the feel of the merino apparently. So with these big bold claims, let’s see what they thought. For the purposes of this test, I bought the altitude zip base layer.


  • Is it comfortable? Of the three garments, these guys claim to be the most comfortable and they are spot on. You almost feel like you’re wearing silk so thin and lightweight is the material. The fit is also very good, which while ‘figure-hugging’ is also loose and stretchy so that if you’re a ‘MAMIL’ on one of those pointless road bikes that some runners seem to like doing, your belly won’t be too much on show. The torso, like the Icebreaker fits long too. 9/10
  • Is it practical? In this instance, highly practical. It has a great collar for stopping the backpack strap rub, as well as some nice ‘half-hand’ warmers if you forget your gloves. This is a nice little addition, and I note that Icebreaker seem to have recently introduced this too, or at least it appears that way. 9/10
  • What’s it like in different conditions? This is where I find the I/O falls down a little. I sometimes felt like I was wearing a wet rag, which was strange for material that felt so fine and thin in the dry. Maybe it’s just me, but if I know it’s going to be a wet one out there, I probably steer clear of this one in favour of the Icebreaker. 7/10
  • How much does it cost? This one’s slightly more expensive than the Icebreaker at $94.50 kangaroo dollars, but that’s to be expected with the additional features you have over say the basic icebreaker model. I don’t mind paying that additional though because I actually use this for more than just running, it’s quite a nice top to wear everyday too.
  • What’s it best for? A really good choice for the warmer weather given how light and comfortable it is. Also good for long runs of five hours plus where the practical elements of the top come into play. Not so good in the wet.
  • Total score: 25/30


The very posh, high-end Ashmei carbon jersey (not a top!)
The very posh, high-end Ashmei carbon jersey (not a top!) (Pic: Ashmei)

Next up is the extremely high-end Ashmei brand based in the UK. I’ve worn a number of their items now and you almost feel guilty taking such a nice piece of clothing out on the trail. This stuff looks and feels very posh, and it’s the kind of thing you could see an investment banker having as he pretends to be a trail runner 🙂 No offense to investment bankers, except of course if you’re responsible for screwing over our economy 🙂

Anyway, politics aside, let’s see how this high-end brand fares. For the purposes of testing, we were sent the Carbon short-sleeved running jersey.

  • Is it comfortable? This one sits almost on a par with the I/O top, but maybe half a point behind as the material just feels that little bit ‘thicker’, even though the top feels very lightweight. It’s also a lot shorter in the torso than the others, which for someone like me means a bit of pulling down as it rides up my back with the backpack on. 8.5/10
  • Is it practical? Probably the standout performer, and at the price it sells for, so it should. You could wear this top on a posh night out. It has a very sleek collar, a nice red stripe across the chest, zip neck front and a handy little pocket on the side which perfectly fits an iphone. 10/10
  • What’s it like in different conditions? Very good in the wet because as the title suggests, has the addition of carbon into the top which increases the performance of the wicking and drying ability. This was very much the case on a few runs I’ve had of late where parts of it will see me sweating profusely, but the top drying within 10-15 mins in shadier parts of my run. It’s a top that I would be comfortable wearing in 30+ degrees of heat too. 9/10
  • How much does it cost? The most expensive of the lot at 75 golden pounds, or around $130 kangaroo dollars. Is it worth it? Not sure, I got mine for free (disclaimer), but on the face of it, I probably would buy it.
  • What’s it best for? Best in those warmer climes with its drying ability, plus the practical nature of the top too makes it a great racing top. I would happily wear this at say a Glasshouse 100kms.
  • Total score: 27.5/30


So there you have it, who’d have thought that merino would be so interesting! as I said at the beginning, we’re not comparing like for like, so don’t pay too much attention t the scores in respect of the brands as they all make similar tops of varying degrees. We wanted to show the range of tops that are available and what they might be best for in our humble opinion. I did spend the best part of three months wearing each of the tops, so they were put through the ringer so to speak. We hope you find it useful!

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I'm a mediocre runner who can bat above his average when I train hard. A man of extremes, I do enjoy everything life offers and consider it an absolute pleasure just to be able to put one foot in front of the other and let my mind wander somewhere different.

3 thoughts on “Gear Test: The battle of the Merino tops

  1. Thanks for the review. Like often – you get what you pay for, or so it seems. During my last US trip I bought a Smartwool Merino top. Ended up not needing it during the race but worn it since and equally happy with it as I am with various Icebreaker pieces. No matter the brand – Merino is a cool garment.

  2. I swear by my merino SmartWool socks, and I recently purchased an Icebreaker long sleeve (200) for my trail runs and I am sold for life! I doubt ever wearing synthetic base layers ever again. Here in Canada, we have it all weather wise and merino is the way to go. I only wish the price tags weren’t so high. which is why I hunt for major sales. There is also a new company out by the name of Pep (, supposedly 100% American. Still haven’t tried them yet but looking forward to it. Thanks for the humorous review 🙂

  3. Meh, I’ve had it with merino. I, like lots of others, got excited a few years ago when people started touting the benefits of it as a base layer and was decked out for maybe a year using four five different bits.
    Its either super thin and light and rips on the first tree branch you scrape under, or heavy and reasonably abraision resistant and gets HEAPS heavier and wetter when moving more quickly. Poly-pro outperforms it in every way. lighter, warmer (and instantly warm, unlike wool), dries faster, more abraision resistant.
    I understand those in the northern hemisphere won’t understand what I mean by “scrape under a tree branch” as they run on two metre (or 6 feet 7inches) wide, hardpack trails all day and night, but here in Aus and NZ, out trails are often overgrown and we need a bit of oomph in our gear.
    I do love it when people say “I can wear my wool thingo for 5 days without stinking”. They cant, and they dont, or if they do, they don’t run with other people much. Wool stinks like everything else.
    Stripes forever!

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