Mine’s on a 20″ wheeled Airnimal Rhino. I’ve used it for commuting and the occasional off-road at Swinley. I love it, particularly the shifting when stationary, coasting, whenever. Range is a little limited and there is a significant jump in ratio from 4 to 5.

Interestingly, I prefer the Shimano shifter to the Rholoff, but I found wheel removal was a pain. Actually it was wheel replacement, as getting the shifting plate back on the wheel before reinsertion was “interesting”.

Might change the 29er SS to Alfine one day if the 11 speed is as good as expected. For commuting bikes, I can’t see why anyone would not use hub gears.