I've got the Posi-Quiet ceramics and installed them myself with just under 5,000 miles on the car. I did not turn the rotors. There is virtually no dust at all, I've never heard them squeal, and braking performance does not appear to compromised at all since a weekend of track duty showed them to work perfectly. Said track day included a heavy braking zone taking me from 125mph to 35mph on every lap and another 115mph to 30mph braking zone. I highly recommend them.