Don't waste the money on a hub-motor go with a mid-drive.
Why mid drive when the guy is trying to go 22mph with a single speed?
The mid-drive will do everything a hub-motor will do with more climbing ability, less possible heat build-up, and isn't unsprung weight. It can also be switched to another bike when the guy realizes that he doesn't really want a single-speed ebike. Mid-drives can have throttles too but put the torque into the chain where it was designed to be applied.
No heat issues? What about if the bike is ever ridden... you know, up hills. Real hills, maybe even on a hot day. How could you possibly notice sprung, let alone unsprung weight if you pound around on a hub-motor ebike? There is a huge difference in comfort ask any hard-tail Harley rider. Less money and less capability, more wear-n-tear on the wheel, motor and anything carried on the bike. Less work? I can change a flat on my rear tire in about 15 mins on the side of the trail, how about you? But you have to understand that we are comparing apples and really really good apples. A mid-drive to a Rohloff Speed-hub on a fully suspended frame designed to carry lots of weight can hardly be compared to a <$2000.00 ebike, especially one with a hub-motor. More like comparing a KIA and Maybach. And, "world saving mid drive ebikers"? I have no idea what that even means.
