I am just joining this site, albeit a little late in the game.
I always had the dream of going full-time and had quite a bit of experience with a bunkhouse travel trailer when kids were growing up. Then, two different motorhomes when we were growing up. My dream was always to have a big 5th wheel with an MDT. When we went full-time (Jan 2020) we bought a New Horizons Majestic 43' with 4 slide-outs (GVWR 26,000lbs) and an F450 King Ranch long bed dually. After driving across country and experiencing the mountains in CO (Wolf Creek Pass) and elsewhere and lugging the steep inclines at 25mph, smoking brakes on steep, long downhill runs, it scared my wife enough that she agreed that maybe we needed a bigger truck.
I already new I wanted an HDT, but my wife was thinking MDT. Once she rode in an MDT she realized that it was no more comfortable than the F450 and that she didn't want to drive it running errands. At that point, the only other option was the HDT for me with a smart car for her.
I found a converted 2006 Volvo VN630 hauler on a ranch. It is the low sleeper model, D15 Volvo engine with 465hp and 1,650 torque and a 12 speed Eaton automatic transmission. It has an 11' bed and a single rear axle, but is not yet set up for a smart car. I sold my heavy duty 5th wheel hitch with the F450 and the truck only has a gooseneck. After much research and discussions with some experts, I decided to change the 5th wheel pin box on the trailer to a gooseneck adapter. The gooseneck ball on the truck is welded on a base plate with three airbags (identical to the 30,000lb Trailer Saver hitch I had on the F450), one in front and two on rear, so I have air bag comfort on the gooseneck ball.
I decided to go the gooseneck route based on three things.
1. I knew that any hitch currently on the truck would eventually have to be moved to the very back of the bed in order to fit the smart car. So, if I didn't like the gooseneck setup after traveling around the country for several months, then I could switch back to a 5th wheel hitch when the smart car conversion is done.
2. Initial costs. I figured I saved around $3,000 by going with the gooseneck, between the difference saved on the Gen Y gooseneck hitch versus the Travel Saver 5th wheel hitch, plus removal and install labor for the 5th wheel hitch.
2. My research showed that the gooseneck is at least as good, if not better than towing with the 5th wheel hitch. Some folks have even claimed the mileage improved around 1 mpg.
We are currently stuck in AZ, where we spent the Winter because we had a blowout, the debris from that broke the air valves on the other two tires and caused them to go flat. By the time I found a safe place to pull over on I-10 just S of Phoenix, all the tires were ruined. (They were brand new Goodyear G114 H rated with less than 150 miles on them).
So far, we are loving our HDT and would never go back to anything but. Driving an HDT is not much different than driving the F450 long bed dually. The width is close to the same, the height is no higher than the trailer, so the length is the only real difference. My total length is 27'. Although I would love to be able to afford a new Volvo but I like the idea of no DEF and I saved $100,000+ by buying used. If I found another HDT in my price range and already set up with a smart car between now and the end of summer when we plan to have ours done, I might consider that, but that is not an easy task.
Overall, safety and comfort are the primary values in going HDT. With airbags on the gooseneck ball, dampeners on the gooseneck hitch, air on both axles, air cab and air seats, we are comfortable and smooth. With the large air brakes on the truck plus the trailer brakes, stopping power is never the issue. Life is good.