im just offering up facts, dont really want to say one way or the other because i see a flame war on the horizon. i mean on the one hand safety is paramount, but on the other, helmets are pretty darn expensive, so that fine line between critical, and not critical impact becomes pretty important, as long as both of those things are of concern to you. edit: take it to the airport when a friend of yours is flying out, and have him run it through the xray while you watch. then he can hand it to you from the exit.