i had a really nasty spill where i cracked my helmet and had a bad concussion (knocked out for an extended period of time, throwing up, completely messed up for months), and i'd hate to think where i'd be right now if i hadn't had it on. you just never know. shit doesn't even have to be your fault, and knowing that one mistake could be your last...... just seems silly to not err on the side of caution. plus, the set-up i had looked pretty styly, and helmets are really comfortable and warm, so what the hell.