Looking to purchase a set of rear air leveling springs. It would be installed on 2011 Ram 1500 Larime. The question is... what is the best kit for this truck? the Firestone Coil-rite? etc... I was looking to get the kits with the onboard air compresser. I tow a 30ft travel trailer that is approx 8000lbs dry. I really only tow it about 2-3 times a month. What is better, the air bags that go inside the coils or the bags that are mounted to the axel?