I would be wary of either 4 pots or the Minispares ones, the standard calipers will lock up easily in the wet & in the dry if pushed hard. I had 4 pots on mine when I bought the part build but changed them back to standard, they are adequate, but they are not as good as when I had the new style pedal box, but I don't know if that's down to the discs on the rear or the poor design of the old pedal box.
Alan...