I have these
on mine and I love em. Installed in a couple hours. I over-tightened the four carriage bolts that hold the lower brackets to the leaf springs. After a few weeks they snapped. I replaced them with grade 8 bolts and didn't tighten them as tight. No problems now.
I tow a 31' 10k travel trailer and they definatley helped level the rig out. I have a weight distributing hitch, but it still didn't sit quite level. Now it does. I would like to get an onboard air system setup, but just haven't had the time/money.
Now that i think of it there is one issue. The drivers side parking brake cable rubs the upper bag bracket and had worn through the rubber outer layer before I noticed it. There is a steel layer under that, so it was no big deal. I just put a peice of rubber hose around it and it is ok now.