I just saw one of McLean’s crashes on TV today. It was on the Discovery Channel for Monster Garage or Monster Nation or something like that (I wasn’t paying attention to the TV till I saw the monowheel). It showed video of him riding his big V8 monocycle in a residential neighborhood and loosing it during a turn. It did a couple of odd sideways flips and it looked like it may have gerbiled too (the seat goes upside down and tries to do a complete revolution inside the wheel).
It wasn’t a high speed crash. But it was still a violent and dangerous tumble. He could have been crushed by the wheel or the engine.
If you want one you can buy one from McLean. He sells them. Several different sizes from small to big.