Tried on this jacket at an Overland retail store; they only had S, L & XL, so I ordered a M. Came very quickly. The leather is extremely soft, and the jacket is nicely warm; perfect for days when the B-3 jacket is too warm. Inside pockets are well placed.
The fit is a bit close. I wear a 42 suit jacket, but the L was just too loose. The M that I ordered does fit, but while not tight, it is a little close under the arms. Not too tight, and for those who like "trim" or "slim" cuts, it would be fine.
My one complaint is that the zipper is very hard to start. Once I pull it up a half inch or so, it's fine and smooth, but getting it started is a bit of a struggle. Hoping that it loosens up over time. All in all, I like the jacket.