My tentative answer to the first is that as long as you understand that a material can't bend the rules of physics and physiology, then yes – it's a pretty impressive fabric. My answer to the second question, is that for a winter climber the Zion has some problems stemming from its design.
NeoShell's hydrostatic head, the measure of how waterproof the material is, isn't as high as the market leaders' Gore-Tex and eVent but I've found this doesn't mean it isn't waterproof. In desperation to get the first leads of the ice season done, recently I went out ice climbing one afternoon when the temperature went back up above freezing. The weather was making no pretence to even sleeting, it simply rained on us all afternoon and evening. Wearing the Zion over just a base layer, I was impressed to find myself completely dry inside. Not only did the NeoShell keep all the rain out (the outside of the jacket was very wet); the highly breathable nature of the fabric had ensured no clamminess inside from sweat.
Last winter, I was pretty impressed when trying Gore-Tex Pro Shell for the first time, thinking it was noticeably more breathable than earlier forms of that material, but I'm now certain NeoShell is another step up in terms of breathability. As stated earlier: don't expect miracles, a fabric can only let sweat out, not stop you from sweating in the first place, but in the past I would have never used a membrane shell for a highly aerobic activity like running or cross country skiing. Yet I've now used the Zion for both of these. Yes, some sweat does build up inside the jacket (I've even seen some icing along the seam tape after XC skiing on a very cold evening) but when you stop or slow down, it quickly dissipates.
"Not only did the NeoShell keep all the rain out; the highly breathable nature of the fabric had ensured no clamminess inside from sweat."
Polartec explain that the increased breathability comes from actually letting some air through the fabric, making an 'active exchange' that doesn't happen in Gore-Tex and the like. Polartec claims you can't perceive this exchange, although before even reading that I did wonder whether it felt in going out into very cold temperatures as if air was coming through the fabric. But, even if I really could perceive this, the feeling went away as soon as I was warmed up and I've found the jacket completely windproof.
Overall, whilst the Zion may not be as breathable as a Pertex windproof or a stretch-woven softshell, it is not far from being so, and those materials are nowhere close to being as waterproof as NeoShell is. It's notable that the Zion doesn't have pit zips, but I think this is the right decision, as I at least haven't wanted them once.
In this respect, Marmot's decision to classify the Zion as a soft shell is interesting. The material is thick and tough but stretchy. I can climb in it with no dragging or resistance but a gnarly mixed chimney, where my shoulders and back were used a lot, left no mark on the jacket beyond some dirt. The toughness does means though that the jacket is no lightweight at 680 grams in medium. The inner of the jacket is a thin fleece which makes it warm, very comfy against the skin and must also help it to wick.
"I've been wearing it ice climbing with just a merino base underneath and have been fine at temperatures down to about –6 or –7 when active."
In terms of warmth, I've been wearing it ice climbing with just a merino base underneath and have been fine at temperatures down to about –6 or –7 when active. With a midlayer (I've been testing it with the Marmot Variant top) it is really warm, although if you are climbing or hiking fast in anything but very cold or wild conditions you may overheat. I know some people still take a lightweight waterproof along with a soft shell into the mountains, but with the NeoShell I don't think this is necessary, and the Zion's multi-role nature is definitely its strength.
Little things like the 'zip garages' work perfectly and drawcords all work fine one handed. The pockets are well laid out and work with a harness and little flourishes like the 'port' to allow a headphone cable to go from inside your jacket to your iPod in your chest pocket are both cute and work well.
But unfortunately there is trouble in paradise. I feel the hood design rather lets down an otherwise very clever jacket. This is coming very much from the perspective of a climber (but then this is a climbing website!) - the hood is simply too small to work well with helmet. You can just about get the hood up over a helmet, but then it is impossible to zip the jacket up fully without seriously crushing your face and stopping all neck movements! As even many skiers wear helmets these days, I can't really see any logic to making a serious mountain jacket and then putting a non-helmet compatible hood on it?
"There is trouble in paradise. I feel the hood design rather lets down an otherwise very clever jacket."
Even more oddly the hood is a pretty serious design in that it has a stiffened peak (although I think they work better when the drawcords go all the way around the hood rather than just up to the start of the peak). It's substantial nature is noticeable when for instance you are putting a belay jacket on or taking over-the-shoulder slings off, so you have the hassle of a big hood without the full benefits. The hood my Marmot Alpinist hardshell is fantastic so it's not like Marmot don't build great mountain hoods – they have just chosen not too here for a reason I don't understand.
The Zion is a nice jacket made out of impressive material but I can't help feeling Marmot have missed a trick here. It truly is a 'waterproof softshell' which means you should be able to dump your hardshell and rely on this as an outer layer for all mountain conditions; but until it has a fully helmet-compatible hood it will still be something of a compromise for winter climbers. We are getting closer to the perfect winter climber's jacket for the cold but often soggy hills of the British Isles, but we're not quite there yet.
Toby is based in Finland. He describes himself as: "a writer and researcher specialising in international security politics; finally no longer a PhD student; hopeless but enthusiastic climber; part-time gear reviewer; keen multi-role cyclist; idealist and cynic"
Climbing keeps him from getting too depressed about politics. He blogs about both at:
See this product at the Joe Brown - Snowdonia shop