I wore out a set of gears at ~4500 miles. No gears available for that brand.
Another hub the connector to the wiring harness burned off in the rain because the pins were too close together for 48 v. Was able to repair that one by changing connector. Weird selection of colors of wire delayed repair 18 months until I was able to disassemble the hub and identify the function of the wires. .
Another hub, 36 v 350 w, was too small for the 60 lb groceries I carry (I weigh 160) and the windings shorted climbing 12% hills with too much voltage, 48 v.
All these were front hubs. I don't like too much weight on the rear.