I just bought one last weekend after weeks of looking at all types of half helmets. It definitely looks better than any of the other DOT helmets, although I still look better with a full face shield. The quality seems very good and it stays on my head at speed with no problems.
As for sizing, my melon is in the 22-in/56-cm range and I bought a Large. Interestingly, I also bought a Medium for my 10-year old daughter and we mistakenly switched helmets at one of our stops. The only reason we noticed was she saw the M on the back of my head once we were underway. There's a fair amount of padding.
I was originally looking for Nexl helmets, but never found a retail outlet. They seem smaller and are DOT, but are way expensive. The Skid Lid was $40 vs $130+ for Nexl.
After riding with a full face helmet, the half is a whole new experience that I'm really enjoying. It's pretty obvious it won't protect me as well though.
