Really depends on your budget and your use. I've owned both and bought both new and used. I'd rather have a new gas coach as opposed to a comparably priced diesel that's going to be 6-10 years old. Once they are parked there isn't a lot of difference between a modern gas coach and a diesel coach. If your use is tailgating, the occasional trip to the Gulf and the yearly trip to the Smokey's, buy gas and spend the rest of your money on fuel and trips. If you are really traveling, moving weekly, and climbing the Rockies, spend the extra on the diesel. The floor plan and livability is the main concern, you're going to live in it hundreds of hours for every single hour you drive. That being said, diesels ride and drive better.