From JCW Press:

MINI owners world-wide have certainly proved to be keen on the John Cooper Works Kits for the Cooper and Cooper S. The Sussex-based family firm, now run by John's son Mike, has just despatched its 5000th kit, exactly a year after launch.

Top market is the UK with 959 sales, which means that the probably more significant figure for export sales is a remarkable 4041.

Although the kits include items like power mods which add 11bhp to the output of the Cooper and 37bhp to the Cooper S, the most popular lines so far have been the sports seats and 18″ alloy wheels.