I generally get 50 to 60K before doing a brake job so I generally anticipate the change and watch for deals on the pads, rotors, sensors, etc and put everything on new. However If the rotor is not worn down too far I see no reason why new pads will not seat to the existing rotors. Granted each pad and rotor will wear differently and there may be some what less performance than with everything new, but not a tremendous amount
I generally spend less than $500 to do iit all the way around with the oem or better components, whereas the dealer will want around 2K. I don't mind spending $500 on brakes every 50,000 miles.
