Please, need advise on which air bag or air lifter I should get, I see the Firestone and also the Air Lift. Any real experience? I have seen mixed posts of which one works for the Atlas. It will make a difference? I have the factory installed hitch and towing an APEX Nano 194, gross weight with hitch and cargo around 4,300 pounds and I see the bottom axle of the Atlas lower than the front axel as expected, not a big deal but I guess with air bags on the suspension will improve. Thanks and regards.