You might want to check the manual to see if it gives any recommendations as to maximum acceptable "groove" depth. For some reason .005" sticks in my mind from some other manual... As long as mine aren't warped and grooved up real bad I just hit them with some 60 grit on my DA sander to break the shine and slap on the new pads. And depending on how much a replacement rotor is I might just toss them.

I remember I did a front brake job on the kid's 92 Chrysler and before having the rotors turned (he let them go too long) I called the parts house for grins. I thought I'd scare him into taking better care of the thing but new ones were only around $15 each! Seems I remember getting them turned would have been $10!

Later,

Justin