When we first loaded our 1150 AF onto the 2006 Chevy dually we experienced a lot of the same issues you described, What bothered me was when you hit a good dip in the road and the unit would kind of porpoise or the feeling was that the truck would hesitate from the dip but the camper's momentum would continue causing a front to back rocking.
Another issue we have is the slide side of the camper is always heavier that the driver's side.
I installed load stops and this helped but when I replaced a broken air bag and removed the Y in the air lines and ran them independently to the bumper I could control the air pressure on each side and we just finished a 1000 mile road trip from Portland to the Redwoods last week and it rode very well compared to what we experienced in the past.
I'm still going to look into upgrading the shocks, we still feel the railroad tracks and similar bumps in the road, the air bags help but I think a shock upgrade will still help over all.
Good luck!
Bill
