Jacket is lightweight, looks cool and feels well-made. It's definitely made for an average or slimmer build, though. For reference, I'm 5'6" and 175lbs (mostly muscle). Using the one-size-up advice, I ordered an XL. Overall it actually looks pretty good. But it's a little snug across the chest/shoulders. So if you're about 5'6" with an average build (and not broad shoulders) an XL will probably for you perfectly.

I must warn though: the jacket does not have very much flex in it at all. If I were to buy it again I'd order 2 sizes up and get it tailored. Just my two cents.