I'm 5'2" with an average build and I find this bag a bit too roomy. It's hard to find bags for petite sizes though so I'm sure it's no different for most other brands - I just have to move around to warm up the air on the inside initially. I'm a cold sleeper and have used this bag down to about 3 degrees in Iceland. I layer up a bit under it and have no issues with getting cold. It puffs up like a warm cloud and is pretty compact when you stuff it down. I definitely wouldn't want to use it much below 0 degrees but like I said - I get cold easily. The insulated zipper cover is an excellent design feature as I am used to getting cold from the zipper. I use this with my sea to summit Ultralight insulated sleeping mat and they're a great pair!