Love this jacket! I bought one and had to buy one for my daughter so she'd quit borrowing mine! Can be used for dress up or work out. I'm 5'7, 125 pounds and got a medium. Fits great with thin layer underneath.
Prana has really outdone themselves with this one! Ordered the Platinum in a size medium (I am 5'-6" - 125 lb on a good day). I am not wonderfully endowed (34B) but the jacket's fit actually makes me look very feminine! (I suppose that means the jacket would run a little small, but it is just right for me... snug in all the right places.) Sleeves have a super cool zipper down to the wrist. Warm, but still makes me look oh so cool. Collar isn't too high that it makes you uncomfortable. Love it so much I ordered another one for me (just in case something happens to it) AND one for my 11 year old daughter because she keeps stealing it!