My first helmet was a Bell EVO (in HiViz, duh):My helmet is very tight (I guess it fits). It was very uncomfortable at first, but once I realized it was a correct fit and just wore it it didn't bother me at all. I like the full face. I can still get air moving, but I can also nearly seal my head inside (helps when you stop and the bugs are ridiculous). The helmet now fits me like a glove and I'm completely comfortable inside.
Those little half helmets that Harley guys like to wear are DOT approved too, but that doesn't mean they provide equal protection to every other... I don't really understand wanting anything less than full-faced. I can see how stylistically it is wrong for other kinds of bikes, as if that matters, but certainly for our 500s a full-faced helmet looks normal and right.
That's my 2 cents.