This jacket is so warm light and lofty! The only downfall is that I wish I could break it out more often. It has to be below freezing even with only a tshirt underneath, and while standing still (at least that's me). I recently took this jacket, which I keep in the small sea to summit event compression sack, on a winter 4 day camping trip. I could only keep it on for about 2 hours in total time. I honestly only used it to warm up after becoming very cold, and would only have to wear it for about 20 minutes or so to do the job. IMO, one of the best warmth to wallet ratios of any jacket. Not your average warm winter coat, this jacket is not joking. Only reason for 4 stars is because as pointed out by others, the zipper is kinda sticky at the bottom. Haven't tried any zipper products to remedy this yet, but might help.