I put Bilstiens on my 04 Chevy 2500HD 4X4 after 1.5 yrs and was well worth it. The original shocks were garbage!! Absolutely no rebound left in them at all.
Don't count on them solving you chucking problem with your fiver connected, but they defiantly helped the ride and handling both towing and not IMHO.
Ron S, if your reducing your TV tire pressure while towing, keep an eye on your tire temps, especially on the rears, depending on how heavy a fiver your towing. A good solution on a DRW 3500 had been to add Air Bags instead of extra leafs, to give a bit of lift as needed and helps the ride as well. Can reduce when not towing for better ride too.