I wear my helmet most of the time. I always wear it off road (what makes me think its safer on the road I don't know). But I agree with the wearing helmet will help save your life. But then there are people (Tandem Jeremy on STW for one) who say that there is more of a risk of being seriously injured if the helemt catches the ground and can damage your neck through rotational forces. IMO i'd rather get a sore neck than brain damage. But each to their own I guess.
I hate that argument.
Got hit by a van in May, helmet was destroyed and I was knocked out cold. I'd dread to think how badly my eggs would have been scrambled without the helmet. No neck pain either.
I digress anyway, the helmet was a Met, didnt crack but definitely had signs of a big smash.