We sold one at Target a few years ago when I used to work there, I'm pretty sure that every one we sold got returned within a year, completely dead.
For only $300, I'm a bit skeptical about it's potential longevity.
I can't even determine where the motor is in this pic. Might be a rear hub motor, but those are a bit expensive. Looks like it may be mounted friction-style in the little box on the back of the seat tube.