I am a size large in 75% of my jackets; the other 25%, I'm a medium. I like a slim, athletic fit (hence why I'm often a medium when I'm right on the line -- I could wear a large, but it would be baggier than I prefer).
My large showed up yesterday. I looked like Chris Farley in Tommy Boy...fat man in a little coat (I'm 6'2", 185, not fat). It looked like I borrowed it from my 11 year old sister. barely reached my belt, and cut way up under the armpits. When I zipped I wondered if the chest seems would split. I really wonder if they mislabeled a small by mistake.
When I read reviews like this, I always think "hmmm, I bet this person wants a baggy fit and that's why they think its small". Nope. I bought this specifically to layer under a shell that in and of itself is a bit snug. So I want this to be snug -- a sweater, not a jacket.
I feel like an XL might work for me as a snug layer, or XXL if I was looking to put layers under it.
The jacket may perform fine, I wouldn't know -- it just sucks I have to pay $10 to send this back to DoG because of the single most ridiculous sizing I've ever encountered.