Originally Posted by
himespau
Given that they have more material in them, I'd predict that the cheaper helmets might be safer than the more expensive ones. Hotter: sure, heavier: definitely, worse fitting: that's a personal head shape thing, but safer (with the caveat that they both meat the minimum CSPC requimrements): maybe.
Not all materials perform the same. Many higher end helmets use materials that provide more protection with less bulk which allows for better ventilation and a slimmer look.
I tell the customers at the shop I work at to pick a helmet that they are comfortable wearing every time they get on the bike. That can mean anything from ventilation, bulk, shape, fit, to style which IMO is worth considering in a big way. I see (and know) too many people who don't wear a helmet because they don't want to look like nerds.