As this thread illustrates, for anything other than a smaller, non-slide camper, a DRW truck is necessary.
Some may laugh that I have a 1 ton SRW and a Lance 815, but it weighs 2200 lbs. I suspect those who think that have excess capacity haven't done the math carefully. With me, the gf, two dogs, and some food and clothes on board, we are right at capacity.
I also laugh at those who have massively overloaded trucks and think that different wheels or tires are enough to make up the difference. I that was the case, why would heavier-duty trucks come with heavier duty components? Why would an F550 or Ram 5500 have bigger brakes, axles, etc. if all they needed was the 19.5" tires and wheels? Answer, they wouldn't--a truck is a system. While you might be able to remove the weakest component and replace it with something tougher, the fact is that you are taking additional risk and causing more wear to your truck by overloading it. Even if the law won't prohibit doing it, it doesn't follow that it's a good idea.
We're not the only ones doing it, btw. I saw plenty of 38' 5ers behind 3/4 ton trucks this past weekend at the RV parks. Care to guess if they're over their GVWR? The dry pin weight of one of thse 5ers alone tells the whole story.