Arrived today, looks and feels quality. Not used yet but as I found the sizing comments helpful so wanted to add my own thoughts. I am 5'10", 13stone 5lbs, 37 waist, medium build. The XL is a great fit for me. Is good over 1 or 2 layers. It is not a close fit over a T shirt and will be very slightly "flappy" but unless you are mad keen to have racey road bike tightness I think this size will suit a lot of people.