This is a great and timely discussion for us. We have driven a lot of miles and spent many months in our gas coach (we are 3/4 timers). We feel very comfortable fixing or getting repairs done on our F53 chassis. We'd enjoy getting a bit more living space in the front of our coach and truly the only way to do that is with a heavier coach as our Thor Challenger is at the high end of the weight range for a F53 chassis. So with that in mind a DP would be the best alternative.
Now the issue.
We have twice traveled to Alaska via the AlCan Highway in a large SUV. Contemplating another 10,000 mile road trip next summer via Vancouver to Fairbanks and return via AlCan. I am 95% comfortable with fixing virtually everything in our Challenger - either drive train or household. Not sure I'd have the same comfort level with a DP replacement. When you are 150 miles from a repair shop, you are kinda left to your own devices. And I know from previous experience that the trip can be hard on any vehicle. If we were to move to a DP it will probably be after that trip.
Just my thinking.
US Army Retired - loving it in our Challenger 37TB.