It is possible to cut slotted rotors, but you should be able to just run them down to their limit and replace them when they are out of spec.
As pointed out by OMG, the slots just improve performance but they still work just like regular rotors. The pads just pass over the slots, they don't work like a cheese grater, lol.
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2004 S60R - 350+ HP, AWD, Custom FMIC & Exhaust, Active Suspension & A Big Set Of Brembos
Crazy Camber, Stretch & Poke; its the new triple-stack-bleacher-wing ricer fad that's all the rage nowadays, lol