Not super impressed after 2 years
This bag is wicked light - which is why I wanted it in the first place... however, It's not quite as warm as I hoped. I use it with a THICK thermarest camp rest and inside an OR GoreTex Bivy. I sleep very warm typically, but have been chilled on a few late september trips where I doubt the temp dropped much if any below 40 degrees. Had to put my down vest in with my feet. There was a bit of wind exposure in both cases. With my wide pad in the bivy i get cold spots where there's any pressure on the bag. Still a good bag and works well up to September as long as you don't get a cold front. I'm used to temp ratings in my Western Mountaineering bags easily exceeding the rating so was slightly disappointed. If weight's your main deal and you don't intend to push the rating this is still a fantastic choice. If you're thinking full 3 season bag (October) in the rockies, better rethink and get a 20 or 30 degree bag minimum.