They are only about 20 minutes south of where eimports is located right on Route 611 south of Doylestown. Follow Rte 313 south to Rte 611 and go south about 10 more minutes. Their service department is open until around noon on Saturday. They are a relatively small, low-key dealership (compared to Brandywine where I got my car) with pretty knowledgeable staff. Doesn't hurt that Bob Holbert was a legendary Porsche race driver back in the 60's.
http://holbert.porschedealer.com/