Any pressurized tanks or vessels have a finite lifespan. The multiple cycles from high to low pressure over time cause stress fractures in the tank. Take scuba tanks for example. They require periodic testing to certify that the tank is still safe to be filled to over 3000psi. That said this car not only would cost stupid amounts of money but would also require specialized expensive lifetime maintenance. Lastly as for the rocket flips and insanity I can only see that making sense to use in one scenario and that is a collision detection and the jets fire and the billionaire driving is magically saved and does die.