One of the reasons we traded back in '07 was Newmar had expanded the use of Comfort Drive across the entire diesel line - best move we've ever made in our RV life.
We did a 5,500 mile Yellowstone run in 10 days a few years back. We do a 10 hour run to Richmond Virginia a few times a year with no worries.
We used to have a TT as well as our MH. A few years ago we were doing a group gathering. I towed the TT the 1.5 hours to the campground, then drove home to get the MH. The TT was set up with all the best towing equipment, plus my truck is a Super Duty diesel. On the way down I was thinking how much $$$ we could save if we kept the TT and sold the MH.
When I got back on the road with the MH I was about 2 miles into the trip when I said to myself "what the heck were you thinking?"
The TT is gone, the MH isn't.
If all we ever did was short local trips I think a TT might work. For TRAVELING its tough to beat a MH.