Does it balance itself side to side, or only front to back? At 20 mph it's not all that useful. Even if it is street legal, I would not consider it street safe. I don't want to be on a contraption that's open to getting knocked off when cars are going by at 40 mph (common on our 35-mph streets) and I can only go 20. OTOH, it's probably no less safe than a bicycle. (Which I do not ride in traffic!) It looks cool, though, for tooling around in low-speed areas.