UKH

I'm looking to get a new mid layer for the coming winter season and have been toying with the idea of getting something a little more plush than my current softshell jacket. It won't be worn for the walk in, only as a climbing and wandering back out jacket. I tend to run warm when I'm moving but cool down quickly when stationary. 

My original thought was to go with the Nano Air as it seems more breathable from certain reviews, but the Atom LT also has a big following and Arcteryx generally fits me better. 

Anyone used both or either as a midlayer for winter climbing and can comment what they thought? Or any other similar alternatives?

In reply to Nathan Adam:

Sorry can't help with the Atom LT but I use the Proton LT for pretty much what you are wanting https://www.ukclimbing.com/gear/clothing/synthetic_insulation/arc'teryx_pro...

I was pretty sceptical when I got it to review but I've used it a fair amount over the last few winters, although I've found over a base layer I can often walk in wearing the Proton quite comfortably (I warm up and get sweaty easily but it seems breathable enough in cold and windy conditions). Then under a hardshell its a really warm mid-layer. And of course being Arcteryx, it looks pretty smart just to wear about in cooler weather.

I'm not sure if the Proton is meant to be warmer or less warm than the Atom though?

In reply to Nathan Adam:

Proton LT, in fair weather I just wear it over a baselayer while winter climbing, feel it sheds water and snow pretty decently, the fit is v good for climbing I also often wear while rock climbing when it's single digits as well as walking/scrambling around up high especially when it's windy but you're generating bodyheat by moving, feels like the perfect level of breathability 

In reply to Nathan Adam:

I've used both in the past and can't say theres much of a difference. Currently got a Micropuff and a Nanoair gillet which I'll layer in some combo with a fleece and base layer under my Goretex when it's actually cold. The nanoair stuff is probably the most softshell like, but you can certainly feel the wind through it and it doesn't do as well in the wet as Primaloft. 

In reply to Nathan Adam: I'd think hard about what you want the jacket to actually do.  I have a NanoAir jacket, and like it a lot as a mid layer when it's cold, but it's an insulating jayer i.m.o., with almost no windproofing, and something I'd wear under a softshell, rather than as a replacement.

The LT is a bit more 'all round'

In reply to TobyA:

As I’ve seen it from researching all three, the Proton LT seems to fit a nice gap between all of them. I think the Atom LT will be too warm for what I’m after, but typically with a big voucher to spend in Cotswold they don’t stock the Proton LT!

Most reviewers seem to rate the Proton a bit higher than the Atom. The Atom seems to be more of an all round piece/light belay jacket rather than something for layering. I usually just try and climb in 3/4 thin layers, anything more than that and I overheat and get soaked with sweat. 

In reply to LucaC:

The idea of wearing a Micropuff and a fleece with other things under a hard shell is making me feel sweaty already!

In reply to wbo2:

I’m looking for something to be able to breathe really well, but means I can dispense with having loads of other items of clothing along with me. In that regard, I’m not worried about the lack of wind resistance for the Nano Air as it’s only ever going to be worn under a shell jacket or wind proof in the summer.

My other thought was to dispense with a thermal base layer, go with something lighter and then have an Atom LT underneath a hardshell and that would serve me for the bulk of the time. Belay jacket over the top of course when stationary but I’m already happy with that part of the system. 

In reply to Nathan Adam:

I've used both but only the atom on Scottish winter. I wouldn't use either as a mid layer as you'd be too warm imo. Although for reference I normally climbed in a base, thin fleece and shell. I'd occasionally wear just the atom over a base if it was dry and cold.

The nano is maybe warmer if anything, but without the wind resistance. Also worth noting that on dry, cold and windy days the atom was next to useless because of the totally unprotected 'breathable' patches from armpit to hem (unless theyve changed that design in the past 5 years). 

Hth

In reply to Nathan Adam:

The proton is a tougher material than the atom in my experience. Definitely a hardier jacket

In reply to Nathan Adam:

I would go with either the nano air, the ME Switch pro, or Kinesis 

I had one of the older Atoms, it was quite nice, but only used it for casual - the outer fabric doesn’t stretch much and was a bit restrictive in the arms and they were a bit short too. I felt it had more of a casual fit. They also pack down really quick. I dont really get on with the new Arcteryx stuff since they were bought by Amer sports, seems they have focused more on fashion, there are less styles and colours and they have dropped a lot of good designs.

the Nano Air is nice - although the new fit is quite different from the original, they are super comfy to wear and very stretchy, the fabric is quite delicate but Patagonia will repair, and they let all the wind through. Might be quite warm as a mid layer in Scotland , if you can find one the Nano Air Light is great as a mid layer, but in classic Patagonia style they discontinued it.

the ME Switch and Kinesis are my preferred choices these days - switch is lovely, under layers and as an outer, and the Kinesis works very well as a mid or outer, works well when wet too. Both are stretchy, light and comfortable it most conditions- I’ve been particularly impressed with how breathable both jackets are, and they rarely feel cold.

In reply to Nathan Adam:

I have the OG Nano air, no idea if this is the same thickness of insulation as the current version.

I really like it,  it's lovely to wear, good "handfeel"* and I wear it a lot. I bought it as a winter outer/mid layer. My "system" is ME Eclipse, Nano Air, Softshell or Gore-Tex, Belay Jacket. Works really well. The nano air "breathes" surprisingly well, far batter than my nano puff (which feels actually "sweaty" in comparison) and even though by the end of physical lead I am hot, I am less sweaty than I thought I'd be.

On the downside, it's outer fabric is quite fragile (mines covered in betrafol/duct tape) and it's not very windproof. It's also still pretty warm, so not great in the summer if you actually move in it.

*I think that's the industry term

In reply to Nathan Adam:

I use the atom lt as a mid layer but am about to switch to an ME Concordia fleece as the atom ( and in my experience the montane prism) don't breathe particularly well. I do however wear a layer and a half more than most on this thread. Partly a hangover from before belay jackets partly because a hot torso gives hot hands which can let you ditch the gloves for the hard bits ( not on ice!).

I would go for something more breathable. If you don't like wearing your cag walking in you can always add a light windproof. I doubt that there is much difference in weight between windproof plus fleece compared to an atom lt type jacket 

*Just tested it, Concordia with one of those tiny montane windshirts works out at about the same as an atom lt.

In reply to rogerwebb:

Thanks for that Roger. I’m now very tempted by the ME Kinesis after seeing it mentioned further up the thread and like the idea of having a decent hood to go over my helmet. I wear a balaclava under my helmet which gives a bit more versatility than a jacket/base layer with an under helmet hood and stays in position a bit better than my experience with under helmet hoods.

I always have a full change of dry upper layers to get  into before climbing so usually get away with a wind shirt and long sleeve top for the walk in with gloves and a hat to regulate temperature.

In reply to Nathan Adam:

I would be too if I hadn't already got the Concordia...