big-film posted a reply:
For best quality you need to go the Dodge Chrome Imaging. Penn just sends out most of the stuff to be processed by a large house anyway.
There's a drop-off point for Dodge Chrome just West of Georgetown. The cool thing with these guys is that you can get proof prints in any format, and even get proof prints from transparencies. It is well worth a little extra money. Here's the link to their processing pages:
www.dodgechrome.com/photofilm/wetlab.html