I need a new get-me-by helmet after one day on the mini track and see Motorcycle Superstore has the EXO-500 for $70. I'll be getting another Shoei soon, but this deal has me intrigued. I'm 2 miles from the Pony, but can't get down tonight to try one on so I'm curious what other folks think about this helmet. Head shape/sizing is my main concern. The Shoei fit well and I'm a medium. The Scorpion has, as far as I can tell, some sort of air inflating thing that helps snug up the fit? Seems strange, but what do I know? Help?