When you can have this jacket for a fraction of the price? Excellent piece of kit. It's pretty much the same as an Arc'Teryx Alpha SV, but it's not $600 retail. What's not to like?

OK, my only criticism is that the collar of the jacket is a bit rough on the underside of my chin, be it zipped up or not. Somehow it manages to poke me uncomfortably, but it's a small thing, though.

I am 6'3" and 205 lbs, and the XL fits me like a glove. There's a decent amount of room for some layers underneath, but I could not get a down jacket in there.

The fit is more snug & shorter in the leg than the previous version that I have several of, think the new James Bond's swimming trunks. They fixed the waistband issue, too (it would fold over on itself).

There's nothing that beats the comfort of wool underwear, period. I have a bunch of these now, and they are my preferred underwear, summer & winter.

I have been wearing my ArcTeryx Gamma MX for about a year (I love the Gamma MX, it's a fantastic piece of kit) and wanted to buy my father something similar. But I wasn't about to drop the same kind of $ on Dad not knowing if he'd like it or even use it, so when the Shift came along on SAC I was all over it. Well, it arrived today and I am very impressed.

The Shift appears to be a very close copy of the Gamma MX. Very close, but with more useful pockets (ArcTeryx must have a policy of putting the bare minimum of pockets in their jackets. Oooo look guys, we saved a quarter of an ounce!).

The materials seems very similar between the two, both have Polartec, and the cut is identical as far as I can tell. I am 6'3" and about 210lbs, and the XL in both jackets fits me very well: big enough to get as much warm clothing on underneath as I may want but without looking like it is a size too large. They have a very tidy, athletic cut.

If you told me the Shift was an ArcTeryx product I'd have no reason to not believe you. Additionally, the Shift is made in Canada, whereas the Gamma MX is now coming from China. I know what I'll replace my Gamma MX with when the times comes.

Very good jacket, perfect light-weight and 800-fill down makes this jacket a real prize. The fleece lined collar & pockets are a comfortable touch. I'm 6'4" and 210lbs, the XL fits me like it was made just for me. The jacket sits fairly high, but not as high as a bomber jacket. Haven't worn it much to know how well the down will stay inside the jacket. Highly recommended.

OK, so to retort my own critical review ("Grandma's bloomers"), these are the business. Turns out Backcountry must have messed up the sizing chart -- I looked on Icebreaker's website & they had a much more reasonable & normal sizing chart. It says L is my size; no kidding. So I re-order them in L and whaddaya know, they fit like a glove, or, some other thing that also fits closely down there. Yeah, these boxer-briefs are awesome. Get some. You'll understand. Can I give these 6 out of 5?

What is with the sizing? I have a 36-37" waist and normally take like a L in underwear. The guide here says that a 33" waist is a XXL. And that's as big as they go. Say what?!?!

I put them on and the waist is a little snug, but the rest of the brief fits like pantaloons. I feel like a darn pirate. Arrr!

The photos here show the briefs as being snug fitting, well for that to happen, the model / mannequin must be getting cut clean in half by the waist band.

I have a drawer-full of Icebreaker shirts, which are wonderful. What's up with the fit of these things?