The battery ran out 30 minutes into my ride and I had to peddle it home. The placement of the steering was uncomfortably low, my knees banged off the front, the seat was curved so my back was bent, there were screw heads poking through the seat back in line with my spine. I had to peddle extra hard as I were turning the motor as well as the wheels.
I had blisters all down my back when I got home.
These days you're much better off just buying an electric scooter or motorcycle or a modern electric automobile like a Tesla.
I put it to you the C5 is no stupider than a segway, and at one tenth the cost.
Also, "no stupider than a segway" is not a selling point for anything.
I've been thinking of getting one of these because they bridge some rules about motorized vehicles: since you are still peddling you can take them on bike trails, but since the assist kicks in there is almost no resistance allowing you to maintain higher speeds...
edit - but maybe not for five grand