2014 AUDI RS 5 Service Brakes Problems

2014 AUDI RS5 WITH 20,000 MILES W. SHUDDERING OF BRAKES. ON OCT 3. 2015 MY LOCAL MECHANIC TOOK ALL WHEELS OFF AND WE INSPECTED THE BRAKES. VISUALLY WE SAW NO PROBLEMS, NO SIGNS OF OVERHEATING, OR CONCERNS. HE SUGGESTED I TAKE IT TO THE DEALER. ON OCTOBER 9, 2015 I TOOK MY CAR TO AUDI OF ORLAND PARK AND AFTER AN INSPECTION, THE SERVICE MANAGER STATED THAT THE ROTORS HAVE HIGH AND LOW SPOTS, THAT I NEED NEW ROTORS AND BRAKE PADS, THAT AUDI ROTORS MUST BE REPLACED AT 20,000 MILES -HE HAS REPLACED ROTORS EVERY 13,000 MILES ON SOME CUSTOMERS CARS, THAT AUDI BRAKE ROTORS ARE THINNER THAN OTHER BRANDS AND THAT THERE WAS HEAT DAMAGE TO THE ROTORS. REMEMBER THAT JUST 1 WEEK EARLIER, MY LOCAL MECHANIC AND I VISUALLY INSPECTED THE BRAKE ROTORS AND THERE WAS NO BLUING. THE ONLY THING THE SERVICE MANAGER WAS ABLE TO...