They are really good. I've got some of them holding my licenes plate on. You can only special order the screws around here, and what's weird, some of the driver bit sets for the electric screwdrivers and drills come with a few diffrent sizes of bits for them. Just a further or parallel development of the "phillips-head saftey screw" --- Too many people were slashing themselves or their work with flatheads.
I'm still partial to allen heads. I'm just lucky that I've never had to mess with those weird metric sized ones, like 5.7mm or what ever those ones that don't fit anything are.