I absolutely love this and so much that the week after purchasing I got another one different color and love that one tooooo!!!  I would normally buy a large tshirt and after reading other reviews I got this as XL I almost went to xxL and I am glad I didn't.  If you wear a large tshirt XL is the perfect size.  It has a lot of stretch to fit your arms if they are big and if they aren't it would still fit (the stretch works :)....  I am probably going to buy a 3rd as well.