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My main concern with cars like this is that if anyone can drive them by telling them where to go, what would happen if some little kid climbs into the car and tells it to take him/her somewhere? Or what if a thief breaks into your car and it will take him/her wherever they want? It seems like there would need to be some kind of identification system (and you probably could just use driver's licenses for this) to prevent things like this but maybe this just shows that I don't know much about these types of cars.