I don't know if I am special or what, but I have never had a bad experence on a Vekoma! I have ridden more SLC's than I can count, way too many boomerangs, an invertigo, two Giant Inverted Boomerangs and Rock'N Roller Coaster. While none of these (excluding RRC) were really fun or thrilling, they wern't really rough either. I have never hit my head once on a Vekoma restraint! *knocks on wood*
I have, however, had headbanging on Arrows before I was tall enough for my ears to go over the OTSR, and older B&Ms.