We like the Class C/B+ because its more like driving a large van. You will notice a lot less storage and space downsizing from a 5er. But, we really like the convenience of traveling in a motorhome.
We have had both the Chevy based class C and Ford based B+. Both are good in their own ways. The Chevy did get better gas mileage (9.5mpg-8.1 liter chev vs 8.9mpg- 6.8 liter ford). Chevy had better leg room.
I think you will enjoy the convenience of the class c....however you will be traveling inside the RV so it takes a little time to figure out how to store stuff to minimize the rattles and noises -).