Many RV'ers have added memory foam topper or an air bed (Aero Bed or Sleep Number) to use on the folding beds.
The biggest complaint is having to fold up the bed or unfold it. Most RV'ers prefer a always made up bed.
We dealt with folding beds in or first two RVs. It was a necessary chore to fold and unfold the bed so it wasn't that bad. However, I sure like our current RV with an always made up bed.
You may want to consider a Class A with a walk around bed. They are about the same as a class C to drive and you get more usable living space when compared same length class A vs class C