When we purchased our first TT, we towed with a Chevy 1500 Suburban. We thought that was adequate, until we burned up the transmission. At that point we had to make a decision. Not knowing what our future held, but knowing also the one constant of life .... (things constantly change) ... we debated "how much truck" should we get. We debated, asked a few questions, and finally came to the conclusion we wanted something big enough, so if our needs changed in the future we would not have to buy yet another bigger truck. So we decided on a 3500 duly (gas) Chevy Silverado, with the help and suggestion of our GM mechanic.
From that point on, it was only 3500 duly's. Good choice too, because we eventually got a diesel 3500 duly and got a much larger trailer, and then got the second duly (the one we have now) when the body was beginning to fail on the old one.
There was no way we could afford a NEW one. So the first and second were purchased used from a dealer. The resale was surprisingly pleasant for both vehicles. The 3rd one we own now, we purchased brand new. Our finances are now much stronger, and it was just time for something brand NEW.
So, what I'm suggesting is .... really .... just get a 3500 duly and then you can town just about anything, and definately NOT have any problems with just about anything under 12,000 pounds (TT or 5er or HTT or Toy hauler TT or Toy hauler 5er). Plus you have enough tow capacity if you ever decide to get a boat, and a 3500 duly will pull a LOT of boat too, and about any size utility trailer (covered or open).
Bottom line ... go big and you will never ever again have to worry or even consider what you are towing.