We had a small Class C (cabover bed) and wanted a C with "bed down." Certainly as a couple we didn't need a cabover bed along with the rear queen walkaround, the dinette bed and the jacknife sofa bed. BUT we wanted more storage than we'd had before and found that the (so-called) B+ is lower and narrower than the "full" Class C. Lower and narrower would have been fine but to get some storage we went to the "full" C with raised house floor which makes the coach taller, and "wide body" design which makes the coach 101" wide vs. the 96" that Class C used to be and many B+ now are.
"Super C" is another marketing label...