Tried the new XC/trail helmets from Kali Protectives, as well as the SixSixOne Recon, and was stuck right between the S/M and M/L. Neither brand fit in either size. Then tried the Striker in L/XL. Amazing. Fits better than anything I've ever tried before. No battle scars yet, but on fit alone this helmet wins by miles. Light weight, lots of vents, and not hard to look at, either.