Ultimate safety would be a properly installed cell, but, the government requires the gas tanks of cars to take a hit without rupturing. I backed into the wall at NHIS and completly crushed the rear of my RX-7 and crushed the tank. Not one drop of fuel leaked. Alot of cell instilations are sub-par and are more dangerous than the stock tank instalation. One side note, I have been a volunteer Fireman for over 25 years and have gone to hundereds of car accidents and car fires. I have never seen a car fire caused by a gas tank rupture, or an explosion of a gas tank during a car fire. Not saying it dosen't happen, just that it's rare.