I'm just putting this up here to populate the list. I have not been to this shop enough to recommend it to anybody.

Business Name: Mach V Motorsports/Ultimate Performance
Full Street Address(Street, City, State, Zip): 45064-B Underwood Lane, Dulles, VA 20166 (Located close to Intersection of 28 and 606 by Dulles Airport)
Business Phone Number: (703) 435-5000
Short Description of Services: Mach V sells a wide variety of parts for Subarus and Diamond Star Motor (DSM) Applications, including the Lancer Evolution. They also carry parts for the SRT-4. You can buy stuff online from Mach V. They teamed up with Ultimate Performance earlier in the year so that they can provide installation services for the parts they sell. Ultimate Performance works on pretty much anything, domestic or import.
Optional Contact Person Name: Dan @ Mach V, Norris @ Ultimate
Optional Contact Person E-mail:
Optional Website Address: http://www.fastwrx.com, http://www.machevo.com, http://www.srtoys.com