I would *strongly* recommend against carbon fiber if it is hanging down near the bottom of the fascia. CF is strong & light, but it comes at the expense of brittleness.
ABS plastic can take some serious damage, yet with a little hammering and a heat gun, you can get things shaped back into working order. One important thing Bobby's kit also includes is screen mesh - which will keep you from filling your rotor vanes with dirt clods, tire rubber, or dry grass that will catch fire in 1400 degree brake rotors.