It works fairly well for me, though as others have mentioned I use it more as a wow thing for passengers since it's a bit slow, though it's surprisingly good at getting into tight spaces, a process that is pretty cool to watch.
It only scared me once during a perpendicular park: it pulled waaaay too far forward to back into the spot, and I slammed the brake before it was about to hit the car in front of it. The car had a really glossy / shiny chrome metal bumper, which maybe confused it? Not sure, but that was the only time I had any issues, it's otherwise been perfect for me (besides getting it to see open spots at all).