Wheel quality and mileage
The width of the wheels that I have purchased from Roth vary by a millimeter or two. This affects performance of the wheel.
Some wheels purchased from Roth have a ridge on one side. INMHO, this MUST be sanded down. In my experience the ridge wears unevenly and can cause a crack in the Polyurethane.
I have been able to get 150miles max, or about one months usage, before having to replace the rear wheel. This includes roadside motorboarding with varying road conditions.