Many asked about the cross drilled rotors and how they help cool the brake system. Well here is the short answer, air cools them, and without ducting running to your brake discs they are hardly more effective than your standard ventilated disc. The slotted rotors are for gassing, when the pads reach their operating temps or higher they start to gas or breakdown and the slots are there to allow the gas to escape.
So what cross drilled rotors do is reduce suface area decrease co-efficient of friction and are more prone to thermal shock, and cracking unless, you have a specialized braking system using, special brake fluid, stainless steel brake lines, venting all the necessary items to aid in convection
