My Bolle The One sits so low the bridge of my sunglasses fits right against the brim of the helmet. No "forehead gap." It is kinda wide, though.

Kask helmets sit fairly low. The Oakleys fit like hats-- so they feel like they "sit on top." I personally think those Giros make everyone, regardless of head shape, look like an acorn head. They sit high on everyone.

I buy each new helmet by just trying on all the helmets and buying the one that feels the best. I don't look at the prices first. I trend to cheapness, and will sacrifice comfort for cash if I know the price in advance.