I used Mintex red box with ATE power discs when I did my brakes about 4k miles ago. However I am now starting to get a slight pulsing when braking, which is almost certainly warped front rotors. I've used power discs on my 535i with pbr deluxe pads with no warping problems, so I am thinking the Mintex red box may be the problem. Has anyone else experienced this, with either stock rotors or power discs?