Well, now you have. I ride OneWheels and one of mine (all stock except tire) has developed an issue where it does randomly nose dive, even at medium speeds (10-14mph). I'm logged about 2k miles and I'm well aware of when the board can nose dive due to pushing too hard up a hill or into a headwind. I've had 4x nose dives on that board (specifically in the last dozen rides) that were not caused by any of the standard issues. It seems to be a footpad sensor issue since after the dives, the footpad won't engaged fully without some well targeted "precursive maintenance."

Personally, I think a lot of people ride them way to fast for the amount of gear they wear and their skill falling safely in that gear. I like to ride slower and carve. It's more fun and much harder to break a bone if you know how to fall well.