I also have a 2012 RX350 with braking problems. I bought the car at 75,000 miles with the note the the previous owners had a rear brake job at 60,000 miles. Now that I am at 100,000 I need another rear brake job. It was interesting to hear that you tried the drilled rotors with no success. I would be interested in other ideas to fix the root cause of the premature pad and rotor failures.