[Maricopa]

A driver of an FFR spec racer died a year ago of internal injuries suffered as a result of G-forces in a crash. No intrusion, no external injuries, simply the stop did it. Another driver (on the street) was killed in rollover/flip that never even touched the top of the roll bar. He had his neck snapped from the force of the barrel-roll. His passenger was thrown clear and lived.
If you're racing a car you better take whatever you can get, no argument. If you're building a cruiser and want a particular look do what you feel is best. Life is a series of trade-offs and to argue that it's foolish to not have a roll bar when you're driving a car that puts your head 40" off the pavement and gives you 2 layers of fiberglass and 4" of airspace between an opposing car is IMO, missing the point. These aren't safe cars and on the street you're more likely to get an SUV bumper to the upper body or the back of your cranium smacked against the roll bar from a rear ender at a stop light than to roll it over. Yes, anything can happen, but there's no need to tell fully grown adults the facts of life.