I also have R1 Concepts. They are on my Tahoe. I went with slotted and drilled. I did this because slotted helps clear dust from between the rotor and pad surfaces, which helps prevent heating, and the drilled help the rotors cool a little faster, in order to prevent hotspotting/warping which my truck already had when I bought it. I do stop a lot faster too. These brakes have saved me from 2 potentially serious wrecks out here. I don't recommend trying to save money on parts that mean the difference between life and death, but for the price I paid for R1 Concepts, I'm impressed with how good they are.