My wife and I have a Roadtrek on order but we were, at one time, living full time in a new 45' diesel pusher. That thing had everything our former home had. Fuel costs were not an issue because we went from one stop to another and spent at least two weeks there. Our toad got over 40 miles to the gallon. When we decided to go back to a brick and sticks home we sold the big rig, but the RV style of travel never left us. We have friends that travel in a B class RV and love it. The freedom to go almost anywhere was very intriguing to us.
After the research we settled on the CS Adventurous XL 4x4. We live in Utah and a very large part of the state is in BLM land thus the 4x4. While the fuel economy will be nice, it was not the primary consideration in our decision. Freedom is very much the primary consideration.