agreed with dh on this one, we get to see a fair few track and race cars and i smack my head on the cages all the bloody time just moving them around the workshop, any cage that doesnt interfere with getting in and out is probably not going to do a lot (except brain you) and any proper cage that will noticeably stiffen the shell and hopefully affect your chances if the worst happens will see you exiting the car shoulders --> bum --> ankles and then laying in the dirt which is far from cool, oh and it will still smack yo on the head, and hip, and elbow probably