I work for Mercedes-Benz of Bellevue and we use Accutint, located behind Barrier Porsche in Bellevue. They do 1/2 of all of our details and most of the window tinting. They do a great job with the 3m / Stonegard type paint protectant. I have personally seen the 3m job on 2 Porsche Carrera GT's and several other high-end vehicles. Give them a call, and ask for Josh or Kalieb.
Unfortunately I don't have their phone number on me right now. I can update this reply on monday when I get back to the dealership.
Good luck, hope you can make the Mt Baker run on August 27th.
Dean