The Signet-Q is the most comfortable helmet I've ever had on my head. I wear an XL in the Signet-Q, or a XXL in pretty much anything else. Currently wearing an XXL XD-4 with thicker cheekpads and a thin foam shim in both sides of the removable main liner. Seems the Signet-Q is in a league of its own, with respect to shape. I'd love a **quality** dual sport or MX helmet in a Signet-Q fit.