It all depends on your driving habits and the type of pad you use. Powerslots arent bad, TPM and Stoptech are nice also. If you use a ceramic pad (or God forbid organic) with little wear, you shouldnt wear as fast. If you are using a high friction pad (especially carbon-metallic), you are generally going to kill any rotor quicker. If you use a racing pad with a high amount of carbon, your going to literally have iron shreds on your wheels from the pads destroying your rotors, so pad choice is very importat. If your bias is too bad, you may likely warp the front rotors. As it has been discussed before, it is important to consider using a higher friction pad on the rear brakes due to brake bias.
So prettymuch the answer to your question depends on how you set everything up, with a lot of the rotor life depend on your pad choice. If you autoX or drive hard on the street, some life may likely be decreased.