Bought both medium and large, in black.
The fabric is thick and good quality - been buying T-shirts from Sainsbury's and these T-shirts are appreciably thicker.
Haved washed them a few times. The black is still a nice solid black and shrinkage was minimal.
The medium is a close fit in the body, but a little tight under the arm - on me, I find the T-shirt creases between the top of the shoulder and the armpit.
The large seems a little looser in the body - more like a traditional T-shirt fit than a modern fitted T - and the neck is a bit open, not close up like on fitted T-shirts - but fits far more comfortably in the shoulder.
For reference, I'm 6'2", weigh about 14' (90kgs), 42" chest and 38" waist.
Bought from "SkateSlime" - twice - and delivery was prompt, would definitely purchase from them again.