Rotors don't have to absorb heat before they dissipate it, they do have to get rid of the heat and one good way to do it is to not absorb it in the first place. Some heat leaves via the slots, it never gets absorbed by the rotor. Drilled rotors are OK IF the holes are chamfered correctly.
OEM rotors are not drilled or slotted because it costs more to do that. OEM's have engineers that do nothing but figure out what would be less expensive and still perform adequately. That's why they use cheap steel and as little machining as possible, instead of a quality steel like reputable high-end aftermarket manufacturers do. Ford's rotors are not high quality, they warp like the low-end aftermarket stuff. On my trucks, when those rotors warp at 20K-40K miles, they get replaced by decent parts. I usually use Brake Performance parts, and have had outstanding service from those parts.
Then there are the people who still use ceramic pads on trucks. OK for the wife's car, but not advisable on heavier vehicles. Use a quality semi-metallic pad. They'll dust a bit more, but they sure work better.
Go to brakeperformance dot com or one of the other quality manufacturers and read their FAQ concerning rotors and pads.
