JCwrote a review of Arc'teryx Atom LT Hooded Insulated Jacket - Men's on January 31, 2013
Familiarity: I've put it through the wringer
I have had the Atom for about a year. It is the most used piece of clothing I own. The temperature versatility is pretty amazing. I live in the Bay Area and can wear this around town over a t-shirt in temps from 30 - 60 deg F. If I'm moving around a bit in the mountains it can be worn over a light base layer down into the teens, or lower. The stretch panels do breath really well and the jacket is super wind resistant. The fit is really well thought out. I am a big fan of the drop hem in the back. I am 6'2", 225lbs, plus 2 ape index, 46 inch chest, and the XL works really well. Go buy this jacket!