i've been doing a ton of research on this as well. I have a lifted 08 Chevy 2500HD CC 4x4 with airbags, aftermarket 20 in wheels and E rated tires i use for pulling my toy hauler. My TH is an 08 Ragen Fsc2800. My wife is wanting a fuzion 5ver (ok..me too) which pin weight exceeds 3K. I know there are a ton of guys here in AZ and SoCal who tow way over with these 35-40ft THs and i dont want to be in that club.
Since this is strictly a TV, i am buying a dually. I looked at all trucks (2007 +)for towing/truck capacity from 250s to 450's to Kodiaks etc. I am hugely surprised at late model Dodge trucks and their low GVWR. You have to pretty much "order" one to get a dually with over 12,200lbs GVWR (4x4, MC-CC). All trucks since around 2007 have great "tow" capacity from 250s on up but the 5er's PIN in the TH category seem to be going up. Even though materials are lighter and stronger they are throwing in more and more "options" in these. So i am planning for 4-8 yrs down the road myself (not saying i will have the truck that long).
I was pleasantly surprised when i drove a dually (f450) the other day. the longbed made a difference in the ride and the truck rode smoother than expected. I never felt "big" or "wide" driving it. It was also nice not to have to step up into a truck for once (mines lifted). I like the 350/3500s but i dont want to ever have to worry about what i tow size/weight-wise. I know the diffs from the SRW v DRW but i made my choice. Now if it was a DD, i'd rethink this. I know right now i will never make it into my parking garage downtown with a DRW. Heck they had to make an "exception" for my lifted truck and let me park in visitor parking cuz i couldnt make it under their parking signs! :) Anyways..good luck with your purchase.