We have a 2006 Santana Sovereign with a Winzip disc and 10 inch rotor (factory installed) with 1500 miles. We have climbed to the top of Skyline, 1600 vertical feet, and descended via a 5 mile 5 -7% grade using disc brake to control speed maneuvering sharp turns and switchbacks with very hard braking and reacceleration. There was no fade or problems. I have plenty of stopping power with the disc brake and do not see the need for another booster. Do you have the mechanical amplifier in the cable? I have replaced the brake pads and adjust the inboard and outboard pads periodically, but that is it.
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