Justin S.wrote a review of Sierra Designs Flex Down Jacket - Men's on December 14, 2012
I have to agree with the description of this jacket, it is WARM! With just a t-shirt underneath I'm comfortable down into single digits. I mostly wear this for walking around town or going out on the coldest of days. It's still comfortable up into the 30-40 degree range though. I haven't used it much for physical activity for fear of being too hot. Love the fit and feel as well, I'm 6'1", 175 lbs and a Large fits great. I could see this working well at a resort by itself or under a shell if need be.