I suppose any kit would work well, as long as it is not a "soft ride" type kit. It seems a dually is about the only vehicle you'd still want the stiff, HD ride to remain with. You can't afford to give up functionality, to gain a comfy ride.
Looking through a Superlift dealer catalog, they list a 3.5" kit, and a 5.5" kit respectively. Both kits consist of HD replacement front springs, and rear lift blocks. They also include new urethane sway bar bushings, and u bolts.
They recommend a 4" dropped drag link, or 3" steering block. For some reason, they don't list the 4" steering arm for the 1 ton trucks.
They also sell optional shocks for a 4" lift, which naturally you'll need after the lift.
I think the offering from the main suspension manufacturers will be about the same as far as the way the kits achieve the 4" lift.
The "main" being Superlift, Rancho, Pro Comp, and the rest.