I have read up on the ppv brake upgrade, but don't think they are right for me, the 4 piston front brake upgrade from the newest gen standard front brakes seems a much better deal for not spending much more than our stock brakes. they are 13.50in verse our 12.99in rotor and 4 piston calipers vs our 2 piston. Has any here done this upgrade? Seems it need washers just like the PPV system. Thanks!