I have a new Electra Townie Commute, which is basically enhanced beach cruiser with Bosch Performance mid drive, 700c wheels, hydraulic disk breaks, and 8 speed Shimano Nexus hub. It weights in at just under 60lbs. Practical speed limit on it is 19MPH, as you approach 20MPH putting more effort on pedals does not affect your speed but prolongs battery charge instead. So with factory settings the bike trains you to ease off and find the right cadence to maintain 19MPH, this results in using speed 7 on flat surface.

Putting BadassBox on it does not make it into rocket rod, you can comfortably cruise at 21-22MPH, and you can maintain 25MPH with decent effort using maximum speed 8 (maintaining 25MPH will significantly decrease your range though, so I prefer to only use it at certain stretches and not all the time). Sprinting at speed up to 30MPH is possible for short durations at maximum effort, and you need to drop real low on that cruiser handlebar, that really drains your battery too. All this essentially makes it into class 3 e-bike that is still street legal where I ride it.

What I really like about it, is that it sort of behaves like factory speed limited bike at Turbo assist level when you put it into Sport assist with BadassBox. With very compatible speed and battery range, but now you can get speed boost when you need to make that traffic light and (my favorite) you no longer run into speed wall at 20MPH and the entire experience becomes a whole lot more comfortable.