I run EBC brake pads in my Mustang 5.0 and was amazed at how well my braking was at the track. Stock calipers and rotors, but I was amazed at how much my braking improved with just a pad change. My brakes didn't fade after numerous laps over 140 kms/hr . I used EBC yellows up front and greens in the back. They bite hard for the first lil while but improve once they heat-up or after proper bedding.
I put HAWK pads(purple) in my XJ and was also impressed with the results. They don't offer the best modulation on cold mornings or winters and will squeal for a bit, but after a few brake applications it is a marked improvement over OEM stuff.
I would personally avoid slotted or drilled brakes for a vehicle that sees offroad use. I used Brembo cross-drilled and slotted rotors on one of my Bronco's and found that small rocks would get stuck in them and leave huge grooves in my expensive rotors. Some guys I wheeled with found ice would build up in the holes as well. A good quality solid surface rotor is your best bet. I would go aftermarket pads, good fluid, and stainless steel lines.