I have to agree.. Having a good, safe, and of course, fun instructor is more important than the actual agency he or she is instructing for. Most of the "big" certifying agencies (PADI, NAUI, SSI, etc) all use about the same criteria for basic open water certification. When you go above that level is where they start to differ fairly significantly. But, for basic O/W, the instuctor is more important than the agency.