Hi, DO take the time and talk to divers who certified with dive shops that you might be interested in. You may not get the truth from the dive shop itself. My wife and I decided on a shop in Dale City, mostly because it is located only minutes from our home. The owner took plenty of time with us before we signed up. After that it went into a nightmare. While I had no problems with my gear my wife's mask did not fit properly, the instructor did not take the time to get that fixed and from the first class on she fell behind and was not properly trained. By the time we went to the open water certification she still had a badly leaking mask. The dive shop in the meantime did nothing to remedy the problem. I got my certification within a few weeks. my wife was not that lucky. Our first class was in March, by September she still was not certified. The instructor and the dive shop came up with numerous excuses and weeks of "we're not going out, so you won't be certified. Yet every time I went to the Haymarket quarry I saw the dive instructor who had "no time" to spend with my wife for her open water certification. We lost valuable time on our vacation in the Caribbean to finally get her certified.
While I had complained to the dive shop owner, I did not get any help but he of course took the instructors side in the debate.
We also called SSI and they in turn told us that they have no control over the dive shops. (PISSPOOR). Not only did we lose money for a mask with prescription lenses but we also had to pay for certification on the island. I am currently looking for legal help with this dive shop.
On the other hand however, there is a dive shop in Alexandria on Route1 who has been very helpful, knowledgeable and most of all they send plenty of instructors out to "open water certify" their students. Maybe that is why they have a lot of customers and the backyard joint in Dale City has not.
Once again, TALK TO THE STUDENTS if you can, they should give you a more honest answer than someone who is interested in making a buck.