I hear you, Bedlam!
I think if I was going to spend $100k or so on an RV, I would have a hard time convincing myself to get a 4,000+lb TC and a 4500/5500 class truck instead of a 24ft Class A motorhome with a turbo diesel 6cyl (Sprinter chassis) that would average around 15mpg and have quite a bit more room inside! I would imagine they are fairly easy to drive as well.
I guess the biggest difference between the 2 comparisons is the 4WD option with the TC setup. Also- whether or not you can utilize the truck sans TC for other things such as work, farming, towing a car/boat/dump trailer, etc.
