Not every drilled rotors are equal but it is true that drilling will compromise the structure and will create weak points. Also a negative aspect of drilled rotor is that they have a cheese grader effect that eats pads very fast and leave tons of dust. Slotted also have this problem (should be called cheese slicer in that case
).
Looks like dimpled rotors offer a good compromise =>
http://bimmerworld.com/perfBMWarticle.pdf
If you got $$$ carbon ceramic are the best
