Ordered a M. Used it
Ordered a M. Used it for the first time this weekend and it was great! I'm between standard helmet sizes S and M, and the adjustable sizing dial on the back helped fit the rest of the way, even on 40/50 degree days with no headsock/beanie. Only downside is it doesn't have adjustable vents. Comfortable inside padding, and the brim fits nicely with the bolle glasses I got last season.