This shirt @ 3xL and 52" + chest fits me (6' 45" chest) with enough material for a loose fit all round and good sleeve length too.
The material itself might look a bit like washed out denim and feels a bit like it too, it's Tencel which I understand is a modern eco version of Rayon, so no cotton.
It is soft and silky to feel and with the loose fit hangs well on the body. A good alternative to 'xL regular/slim fits' which skimp on material.
As to style, casual, Chino's etc. I'm not going to wear a tie with it.