Cheap Chinese ones have virtually put retreaders out of business. They rarely fail, on the original tread, saving mudguards, lights and hardware. It would take a brave man to retread the case though.
Funnily, the Whoflungdungbrands come and go regularly. Often a new brand will get phenomenally high mileage, for the cost, but once word has got around, the quality has fallen away and a new brand comes out, no doubt from the same factory.

