Rented a Harley near Charlotte a couple years ago and a DRZ400SM near in Pigeon Forge last summer.
Both times just for a day during the family vacation. If its a bike vacation Im probably going to ride there on my Vstrom.
I rented the Harley because it was the only thing available near Charlotte. Had a good time riding to Asheville on the Blueridge Parkway with my FIL (a harley rider).
I rented the DRZ to ride Deals Gap and the area on a free day during a family vacation in TN/NC. This was the perfect bike for a single day ride in that area. Especially for a rider less experienced with tight twisty roads.
I wish it was easier to find non HDs for rent and that the prices were a little better. From what Ive seen price has little to do with the model. It costs more for the DRZ than the touring HD my FIL rode. Even loaded BMWs and Goldwings were only a small price differential from the DRZ.
If I was to do an riding trip in Baja or other off road adventure out west a "rent and tour" would be a nice option. Just getting there would kill many miles and having a tour operator carry luggage and provide mech support would allow traveling lighter. That would be a nice option especially if I could only get a week off at a time.