Rob,
We have a pair of them. We fold them up and keep them under the dinette where they stay clean and safe while we travel.
The seats are adjustable but might be short if you are taller than about 5-10. A 6' friend has borrowed and did OK.
The wheel base is a little strange when compared to a normal bike, and this has caused both of us to get thrown on occasion when stopping or starting (or when our one of our dogs has to greet us).
Do they work as bicycles and beat the hell out of walking in a large crampground - You bet. Equip them with locks and bells. We never had one stolen, but they have been messed with at a KOA. The bell is because oblivious wandering people are not used to the silent approach.
Matt