i wear SMALL in everything and go for slimmer fits. i need an XS on some rare occasions but that doesn't happen often.
the quality is very good, no complaints there. i tried them in small, of course, and let's say i felt like i was trying an oversized medium. the biggest disaster was the sleeves, i would've never needed any gloves to go with it just because i couldn't see my hands. so you got the picture.
and now that i was about to go for the cropped Topman peacoat online, the S is out of stock! what bollox! are any brits willing to help?