Facts that you need to know:
– assist kicks in a few seconds after you start pedaling;
– you are “pushed” up to 25 km/15 mi an hour (once you reach this speed, you are on your own);
– if you drop under 25 km/15 mi an hour, assist resumes;
– there are sensors which interrupt the push once you hit the brakes.
– don’t have a throttle;
– will not assist you if you don’t pedal (there’s a sensor in the crank which detects movement).
For these reasons, you don’t require insurance and license plates to ride them, and a drivers license isn’t necessary either.