Want to upgrade - Is diesel worth it?

I was always told that floor plan is the most important thing to consider first. We have only had 2 class A. One gas and one diesel. The first was a 35 ft gas with 3 slides. Two were in the bedroom and one in the living area. It had the Ford 310 hp. It would go anywhere that we wanted to go. It had no problem going up the mountains on I77 or I81. We now have a 41 ft with 4 slides and a 400 ISL Cummins engine. The gas had everything in it that we wanted at the time. It served us well for four years. During this time we made a list of everything we wanted in our next class A. We found the diesel was better suited for what we do. We average about 8500 miles per year. I, as well as others, can give you our opinions, but as you know, only you can decide.