Right now I'm leaning toward the Class 5 Ram or Ford truck. The current gasoline engines should have enough power but range on a standard tank is limiting. Going to Diesel, Ram currently has the price advantage over a similarly configured Ford. I'm waiting for the next model year specifications and pricing to solidify.
Keep the suggestions coming - Each of us has different expectations of their rig so even if I don't find a Super C for my use, the links provided may help someone else.
Update: I have decided to go with a diesel Class 5 truck. Although I feel the current gasoline engines are powerful, I do not feel comfortable frequenting mountain passes with a GCW over 20K lbs knowing that over the next few years that weight will be over 25K lbs. Because of the complexity and cost of the current diesels, I prefer to keep the vehicle separate from the habitat or garage to keep my options flexible. This choice is also more price conscience than some of my other choices which allows us to camp more often with the money that is not tied up in the rig.