The front discs on my ZX12-R are near the 4.5mm limit after 30,000 miles with EBC HH pads and I need some replacements Does anyone have experience of using PFM cast iron brakes? I'm told they are good stoppers, but as they are iron I'm guessing they rust badly???. Do they warp? Any problems to be aware of? PFM do two types: the "Performance disc" and the "Supersport Upgrade Disc". Not sure which to go for - The Supersport looks pretty trick Any advice or comments appreciated Chris