See this article for photographs of a Smart Car that a friend of mine was driving when he was involved in a head-on collision with another vehicle. The roof was removed by firefighters during my friend's extrication from the Smart Car, prior to his helicopter evacuation to a trauma center.

LI Herald: Crash at Atlantic Beach Bridge

I know the folks who responded to this accident, and they tell me they were amazed at how well the little car protected its occupant. I submit that had he been riding a motorcycle, he would have been in MUCH worse shape.

(I have nothing against motorcycles - indeed I enjoy riding them. Nor will I speculate as to whether he could have avoided the accident in a more maneuverable vehicle - though I doubt it.)