Wrapped rotors at 25,000mi and 20,000mi is an indication that something is wrong.
Possible causes:
* Uneven wheel studs torque.
* Sized caliper pistons or pinched brake hose or defective master cylinder keeping constant hydraulic pressure in the brake system,
* Driving habits? (constant left foot on the brake pedal)
Surface rust does not normally justify replacing the rotors, unless the rotors are pitted.