wore them on a trip to whitney. Started at 11000 feet at 4am with temp at 25 degrees. Going at a strong pace. These pants were perfect. Breathed very well. Had them on until the middle of the switchbacks on the sunny side with temps in 70s at which time I took them off and wore shorts. These fit slim people (I wish people would stop rating clothing and shoes for the fit. They can't make clothes that fit all the different types of American bodies for crying out loud.). Had them on at Forrester pass at 13,200 ft. with snow flurries and they were again perfect-didn't get wet at all. The drawstring was a little weird. They don't have a fastener in front, only a zip fly. The drawstring was superfluous as the pants stayed on well without them being tightened, but the plastic cincher did get under the belt of my pack a couple of times and wasn't comfortable. Small gripe. Great pants for hiking in the high country.

great expedition piece. So much better at insulation than fleece because of the weight and because it protects from the wind. Not waterproof, but does shed water to some degree. Not for rock climbing unless you have something over it, as it is somewhat delicate.

I have the jacket and pants. These are replacing my fleece as an insulating layer on backpacking trips at high altitude. They are so much lighter and warmer.

I hate buying stuff from China. For a thousand reasons that I won't go into. I would much rather buy all my clothing from Arc'teryx (although even their low-end stuff is made in China now). On the other hand these pants fit the bill. Full length zippers to get off when you have your double plastic boots on with crampons. They seem a little delicate, but very light. These companies are responding to the "lighter!" call we as consumers give them. I think with items like this, it is getting to be overkill. One rip on Denali and you'll be cursing them forever.