I have just ordered some of these for my car front and rear. https://www.ecstuning.com/b-ecs-parts/front-2-piece-brake-rotors-pair-340x30/013928ecs01kt2/ The reduction in rotational mass is well worth the price. It frees up loads of power to the wheels. http://www.rightfootdown.com/cars/thoughts/go-faster-with-lightweight-brake-rotors/ And the ecs discs have a bigger reduction in weight. Cant wait for CLP Automotive to receive them and fit them. Might ask for dyno before and after to see the WHP gain.