Take an undersized V6 that is already taxed in a full size pickup and put an RV on it's back to lug around. Sounds like a recipe for disaster to me.
I think they are okay for the average American's need for a pickup (pulling a boat occasionally, otherwise hauling kids and groceries), but not for working hard.
I have done some work to them, they are not fun to work on, that's for sure. That little motor is crammed way down in the frame and under the cowl, the turbos are mounted to the sides in the fender well.