5'10", 183lbs (athletic slim), waist 33-34 in jeans, chest around 22-23".
I bought the 15 3/4 and 33 1/2 sleeve, Tokyo slim fit.
The GSM is def below 130gsm from what I can feel. It's thinner than say Wool and Prince shirts. Of course it's subjective of me so I could be wrong but they don't list the GSM on this website. The price point seems high to my theoretical gsm ratio.
I really like the fit though as rarely do you see a 15 3/4 shirts. The problem is the sleeves are too short and I would say if you're a 33-34 sleeve go for the 35 length with worst case you get it tailored (asian sizing differs from what I understand). But you may not have to get it tailored after a wash (?), not sure but my previous wool shirt from another company did shrink a little.
I bought at full price and probably would still recommend it but if it was on a discount, 100% would rec because of the fit alone not so much the material. It wasn't itchy which is a plus.
The spread collar wool shirt has different sizing measurements so I'll report back on that after a day of wearing.