There is much more difference between the coaches than just the engine. Most diesel coaches have rear engines. That means that all the noise, vibration, and heat are 30-40 feet behind you, instead of right between the front seats. Diesels have air suspensions that perform much better and smoother than the spring suspensions on a gasser. Diesels have more carrying capacity and get better fuel mileage and range (although not better fuel economy because diesel fuel costs more than gasoline). There are many good reasons why a diesel coach costs so much more to buy. Drive them both and you will see. The diesel ride is quieter, smoother and more controlled. Most diesels have larger fuel, water and waste tanks, and more amenities.
This is not to say that a gas coach will not do the job, it will. But it is like asking if you want to drive across the country in a Chevy or a Mercedes.
Marc, Wellington FL
2013 Entegra Anthem 44SL
2018 Lincoln MKX toad
EEZ-RV tire pressure monitor