We have stayed at both parks. We prefer Bear Creek because it is possible to walk around in the park without hiking sticks. As for site size, our first time there we were with a Tiffin Travelers group coaches ranging from 36 to 45 feet in the back ins on the upper level of the park. Everybody got their coaches parked without damage and without undo hardship. One lady who was on her first trip since alone her DH had died asked me to provide ground guidance and she was able to back in on the first try.
Staff were as nice as could be and the location is the best for seeing Asheville and the Blue Ridge sights as well.