Can anyone help with what size I should buy? These will be the first "nice" shirts I have bought (and have never really bought clothes online), and I'm a little confused. Since the black friday sale is final sale, I could really use the help.  Got measured today as follows: Neck:15.5"  Chest: 37.5"  Shoulder: 18.5"   I normally wear a size 31 waist jean. Also, chest size may go up slightly as I have been slacking off in the gym for a while and am getting back into...