This is the best upgrade yet, Airbag + Supercharger Control System. It really raised my RV by about 2 inches and solved the rear track scratch issue. With the air pressure set at 90psi, the ride is so comfortable, almost like driving my Lexus Rx450h (maybe not as good, but a huge improvement). Airbags are considered cheap, under $300 a pair. I did the installation myself, it took about two days to learn and then succeed. There are no leaks at all. The perfect product. I think the control system