As Shane said. I have the AirLift 5000 brand but either is good. Get the onboard compressor either with or without the remote control. Night and day difference in towing and ride for the rig. I literally have to remind myself she's back there.
Play with pressures. Empty I run mine all the way down to 5psi. Loaded anywhere from 40-60 depending on road. My RL is pin heavy however.
Vaughan & Tracy 2013 RW 36RL, 2013 F350 DRW CC, 2016 Focus. MorRyde IS, MorRyde pinbox, disc brakes, Comfort Ride Hitch. "Life is to be embraced, Grab it with both arms ! "