I have broader shoulders and long arms and take a S in the older season GBVs and current Epaulet stuff. most GBV shirts are a little short for me in sleeve length
I prefer epaulet for reasons slack mentioned
All Amok questions:
I own a pair of Amoks in brown suede, purchased last summer. They do squeak, but after a while it's not really noticeable. I sized same in Amok as shoes in 5 last (PA, Strand, etc.)
Hope that helps.
Found the rakuten link if anyone needs more sizing help. Model is roughly 140lbs and 5'5 and wears a size S. Wondering if I should size up to M since I'm 5'11 and 155 lbs... roughly same proportions but taller. Now I'm torn!