RTSKI,
I think technically a Class B is a van conversion like the Roadtrek 190's on the Chevy chassis or Adventurous mocels on the sprinter. The body has not been altered (except a fiberglass roof added). The 200 and 210 models remove the back portion of a stock van and place on a new fiberglass shell. B or C doesn't matter too much what you call it as long as it works for you.
Our RT 190 has the shower in the middle of the van. We use it without worry. Sure the floor gets wet but after the shower a quick swab with a towel and you hae a clean floor. Although we prefer a roomy shower in a campground, the aisle shower works fine and doesn't take up any precioous interior space.
Best wishes and good luck in your search.