We started with an 1140 on a 06 3500 Dodge dually when we tried fulltiming a few years back. Made it 18 months,6 months in the tc, before circumstances called us back home. Never could get it to ride as comfortable as I would like. Replaced it with a 2014 because of the higher load capacity. After upper/lower Stabil loads and air bags, I am happy with it.
That said, it all depends on how comfortable you are with sway while driving. It always freaked me out a bit knowing I had all my possessions and my family in the truck... If you are not changing sites all that often or moving very far, your truck may be fine with the bigger TC. Do not think I would be comfortable with it. Also depends how much time you spend in the TC. We had friends that full timed in a small TC and spent most of the days in the camper...don't know how they did it.
