I was in a similar situation as you earlier, and after ordering about 4 different down jackets, I ended up with a Marmot Guides hoody.
Sierra designs flex - First I ordered, nearly kept it. It was heavy, and not very fitted as I expected it to be. Very big in the torso area.
Outdoor research transcendent - Fit great, but didnt seam that warm. Not much down in the jacket.
Montbell alpine light - Good jacket, but I was still looking for something more warm/durable as this is going to be used around town alot
Marmot Guide - Great fit, plenty of down/loft, seamed to have more substantial fabric than the Montbell, and looked the best for casual wear (transcedent also looked good). I am 5-8, 135 lbs and the small was spot on. Most jackets fit me big in the torso, and small in the arms. This one is cut much better IMO. Fit good over a t-shirt, but I can still throw a fleece/sweatshirt or two underneath if I need. I plan to use it as a midlayer for work, and it layers very well under a medium carhartt. I figure this setup should keep me comfy well below zero.
For me it is definatly the most versitle down jacket I have found.