I have the PacBrake bags. They are stout, and do offer assistance in the sagging area, but I don't really like them for the following reason. I have a Lance slide in. It is pretty heavy, but not overloading the truck. I have the spacers on the front springs, and I wanted something that would keep the truck level when I had the camper on the truck. Due to the fact that the PacBrake bags mount inside the frame rails, I get A LOT of side-to-side sway, and I don't like that at all. I have Rancho 9000 adjustable shocks, and they help, but not enough. I also have the longer rubber gromet stoppers for the helper springs. So, what I have to do is just inflate the bags until the overload springs just separate from the longer gromets, and deal with that. But, I'm not level. I wish there were air bags that mounted to the outer frame rails, and above the overload spring pad. But, until I find a good one, I guess I'll have to deal with what I've got.