I assume the only change was the pads and rotor, and you bedded them in as per rotor pad manufacturer suggested, and you checked rotor runout, and the caliper mounting is correct, then I would say the noise is not a good sign, but a sign of what, I don't know. I would think the drilling would not be a source of your problem, and the slots if mounted wrong direction I don't know. I personally would never drive a car with drilled rotors, slots maybe. The Porsche High dollar rotors have cast holes. The little weight savings vs chance of a failed rotor does not make sense to me. And some pads do not like slots.