I have looked through a bunch of post but there is nothing really clear on what to look for in a helmet. I am not after recommendation of brands etc, just what to look for when deciding for myself. So far i just have... 1. Make sure head can move a little inside the helmet. 2. Clear visor (i'll wear sunnies under if needed) I'll be mainly commuting with it, but a few longer rides of about 1-1.5 hrs. I also might be limited as I have a very narrow head, it's almost impossible to buy sunnies that fit me that didn't come from the kids section. ](*,) What else do I need to look at for when buying?