Originally Posted by ro-monster

I'm not sure where you're getting the idea that only inferior helmets are made of styrofoam. That's what motorcycle helmets are made of, even the best ones. Of course they don't have all the vent holes and the shell is stronger, but the foam is the same material. That said, most bicycle helmets are pretty flimsy, and I think the designers have probably sacrificed effectiveness for lightness and ventilation.

My choice is a full-face downhill MTB helmet, which does have quite a few vents, but also has a much stronger shell and more coverage than a typical bike helmet. In wet weather I switch to a motocross helmet with no vents so my head stays dry. The only downside I've experienced is that people tend to laugh at me.