I have no idea why we see such different results with airbags. The dealer put mine in the 50# range. They did a great job of leveling the suspension but the sway was horrible. I tried different pressure and found that low pressures in the 15# range helped somewhat with level. The ride was better but still bad. I had to bump up the Rancho shocks to the highest settings and then had a very harsh ride. Tar strips on the roads hit hard. I drove for a couple of years and then got Supersprings and dumped the bags. The ride was greatly improved with little sway and I was able to lower the shock settings to a medium level.
I had a 4000# camper on the back of a 2500 Ram so about 7500# on the rear axle. Now I have a 3500 Ram. I added Timbrens to help level the suspension. The ride is a bit soft but I don't see the need for Supersprings.