Have Timbrens on my 2500 CTD. The ride unloaded is the same as not having them. Loaded the ride is good. Would I get them again? Maybe, price is the big draw as well as installation. I think I would get bags next time around if needed. Had bags on a previous truck and they're more versatile than Timbrens. More of a hassle w/o a built in compressor but not that much.
For those that say they ride bad unloaded, that means they were installed wrong. They sit 1" above the axle when unloaded. So unless you're hitting really big bumps they never come into play. Also if the trucks shocks and springs are shot then you could get too much movement bringing the Timbrens into play. In that case springs or shocks should be changed out.