I bought this jacket to wear under my Arc'Teryx Shashka shell for skiing. First, I love the fit and how nicely it fits under the shell. I am 5'1 and typically sleeves have to be rolled or scrunched up -- not with this jacket. The side panels are a stretchy fabric and not very insulating. It does make the jacket fit better, however, the one time I wore it skiing, I kept thinking I felt cold coming through the panels. I love wearing it for other activities or just around the house as a sweater.
Love everything about this jacket. It appears greener than the picture. Also, the sides are a darker color than the rest of the jacket giving it a sportier look. Keeps me warm while out at night or even when my coworkers crank the air conditioning up. I highly recommend this!