I got several pieces couple years ago: mountain pants, mountain shirt, vest, and 90% jacket. The mountain pants came in even waist sizes. Today, the Ascent pants don't. I tried on the Ascents in Medium and Large and either looked like Pee Wee Herman or a rodeo clown. When the manufacturer builds in suspenders, they may as well say one size fits all. There actually is no shirt in this years line. You go from base layer (core or traverse) to jacket. Can't understand this reasoning. I've looked at the Celsius, and would be surprised if it is ideal for motionless tree stand hunting in cold.