Hello Im looking to buy some head gear for boxing, I narrowed it down to the TITLE Platinum Full Face Headgear. But Im a little confused on what size to get. There are two option's regular which is S/M 165lb or less. or L/XL which is 165lb and up. Im 5'9 170LB, the circumference of my head is 22 inches which is a s/m in a flexfit base ball cap. Which size should I got with?