Mach V/Ultimate is the WRX place to goto in NOVA. Also, up in MD there is a VERY EXCELLENT mechanic named Andrew who works inside of a repair facility in Gaithersburg. His reputation is so good that he works on many Subarus both in the DC area and out of the DC area. TurboXS is headquartered in Gaithersburg, and Element Tuning (which is run by Phil, formerly of TurboXS) is in the Montgomery County area as well.