I went with the Radrover over the Voltbike Yukon 750. It looks like the Radrover 48v/11.5ah battery pack can be upgraded with Luna Cycles higher amp 48v/13.5ah or 52v/13.5ah Dolphin packs for more power and range.
I also liked some additional features on the Radrover for the same price like:
- the 3 bottle cage mount points,
- larger hand grips,
- 180mm brakes,
- chain slap guard,
- rear derailleur guard,
- USB port on LCD screen,
- quick release front tire,
- suspension with lock-out mode,
- more comfortable seat with a more upright riding position, and - ability to adjust the max speed to 24-25 mph in PAS 5.
Other than that, the bikes are very similar in price, size, weight, and performance on paper. I might be singing a different song if I had a chance to test ride both instead of relying on fact sheets and YouTube reviews.