I have never liked the idea of balast under the car. If it comes unbolted while under the car, it puts your fellow racers at risk. If it comes unbolted while inside the car it really only puts you at risk. And since you are the one who is likely at fault for the poor install, you should be the one at risk instead of those who had nothing to do w/ the install at all.

That said - I'll be very strick w/ ballast installed under the car.