Well I will say that it looks like Ram has come back around to what worked in the past, just heaver!
That 3500 rear spring pack looks just like the spring pack on my 01 Ram 2500 with Camper package. It also looks very much like the spring pack that is on the 12 4500 Cab Chassis!
I think Ram was working on the equivalent of a production "Long Hauler" before they took the concept truck on the road.
I know my 2500 with factory Camper suspension doesn't flinch at the load it hauls. Ram has been very conservative on their load ratings for years, now they are looking to up the steaks in the ratings war.