I had redstuff pads on my A4 before and they lasted 3 track days and 13,000 miles. I was super impressed with the pads especially with their performance on the racetrack considering they're not meant to be used as a track pad. I switched to yellows and got 1 track day and 7,500 miles and a lot of squeaking and brake dust. I will definitely be sticking with redstuff pads!
Pads are quieter and don't produce nearly as much dust. Initial stopping power doesn't feel as responsive as OEM, but you get used to it and adjust your driving to the new brake feel.
since installing these pads with new stock rotors, i've experienced much better and more linear braking. modulating the brake pedal produces more logical/intuitive braking results.