The problem with the aftermarket mid-drive kits is that very few of them have torque sensors. A good torque sensor transforms the way an e-bike rides IMO. It feels less like an electric scooter and more like a normal bike where the electric assist is given proportional to how hard you pedal. A good hub motor is fine on flatter ground. Where mid-drives shine is on steeper climbs (above about 10%.) They give you the mechanical advantage of the gearing. As the video on the Juiced Bikes YouTube channel shows the Hyper Fat has no trouble climbing. The 30 amps of peak power goes a long way addressing the shortcomings of a hub motor on a hill. Another issue with mid-drives is that many of them cut assistance when you pedal over about 80rpm. Since I come from a road bike background that would be super annoying as I generally pedal 80-90rpm.