Most newer Dually trucks are capable of pulling the heavy 397TH. Personally I like the FORD and GM trucks more than Dodge. I have had some sketchy experiences with Chrysler service departments and tend to stay away from their vehicles because of it.
I started the research into what truck to get about 2-years before we were ready to buy our coach. I did extensive research into all of the vehicles. Knowing that we would be spending hours and hours driving I wanted to get something a bit more luxurious to ride around in. That pulled me into the GMC line. The Denali is as close to riding in a Cadillac as you can get with a truck. It is beautifully appointed and very comfortable. Ours didn't come with the fancy camera system like the FORD's have now days (and the newer GMC's have), but I did order it with the trailering camera package that added cameras in the exact same locations (mirrors, truck bed, behind the camper).
I also knew that we would be going with a Toy Hauler Fifth Wheel trailer that was certainly going to be heavy. That put us into a Dually with a long 8ft bed. There really isn't a safe option for towing a big trailer with anything else.
As far as capabilities go, the GMC 3500HD is a workhorse. It is incredibly powerful. It has the Duramax 6.6L Turbo Diesel that delivers 910 ft. lb. of torque to a rock solid Allison 6-Speed automatic transmission. It has a 3.73 gear ratio, which is perfect for getting the 397TH moving and being able to haul it up the mountains while maintaining reasonable gas milage. Although the diesel and the interior appointments add weight, it still has a payload of 4930 lbs and a trailering capacity of 22,700 lbs.
I know I am biased, but I think the GMC and 397TH look very good together. I see a lot of campers and Dually trucks, but it is rare to see another GMC set up like ours or 397TH on the road.