Below is a detailed article I wrote on the current most popular Ferodo Racing pad compounds:
Which Ferodo Brake Pad Compound is Right for Me?
While a lightly-driven e92 M3 on street tires may be able to get away with DS2500 at Roebling Road, a racing slick-equipped e92 M3 at Watkins Glen or Road America is a
completely different ballgame.
Generalizations like, "stock brakes are great, you just need X" aren't really valid given the enormous number of variables involved. Below are just some of factors that impact how much the abuse your brakes will take on a racetrack. These variables are different for every car, every driver, every track, and every situation.
There is no one single solution that works for everyone. A brake setup you may find perfectly adequate...the next driver may burn it down in the three laps on his car, under the conditions in which he is driving it. In my twenty+ years of working in the racing brake business, I've seen this statement ring true a million and one times.
Driving skill/style (hard or easy on brakes)
Track layout- tracks vary tremendously in how much heat they pour into the brakes
Number of consecutive laps
Speed reached at the end of each straight (related to corner exit speed and horsepower)
Tire size
Tire compound
Suspension setup/alignment (how much rubber is being put on the track)