Those ICE scooters are good for those who maintain the rings in them or use the motor occasionally.
When you first buy a new ICE motor the rings are tight and the bore is new. They really get some good compression. Put a few K on the tacho and the rings leak like hell, The motor blows more smoke and fuel as they age and rider pushes harder to compensate for power loss..
The brushless motor just needs bearing. The smaller bike would be very reliable electronically as they are light, of lower voltage, and you don't need push the motors as hard with the smaller diameter wheel.
We were so close to purchasing A Fly. The Idea of "made-in-factory" has green appeal as factories are more efficient with materials than the DIY enthusiasts.
The size makes it easier and cheaper to ship. What more could you want with a miniature PAB.
Nice concept bikes the Shrinker and Fly are, and an excellent example of better green collage ebike building. Small strong frame, light weight and efficient.