The heat that the rotor prevents from entering into the hub will help prolong the life of the wheel bearings which quickly can wear out do to excessive heat which is produced by the brake system. Another great benefit is that the rotor is able to loose heat much faster allowing it to stay cooler, and allow the brakes to be used harder.
Featuring the Thermo-Graphic paint markings on the rotor allows for effective heat monitoring. When the painted lines change color you can see the temperature that the rotors have reached allowing you to accurately match the proper brake pad compound. The outer drilled rotors have a unique slot and drill design which allows for the gasses to escape that are trapped between the pad and the rotor, which ensures consistent contact.
When the rotor wears out, you can purchase the outer ring separate. This helps reduce the operation cost over the life of the car.
Price is per rotor.