I teach with Al at the same shop. I've been all over the carribbean for 12 years and have never had a problem with an SSI cert no matter what the logo on the Dive shop has been. If the shop only accepts one agencies cert, then move on, as they probably only accept one point of view also. (It's my way or the highway). Guess they do enough business they can turn away paying customers. As far as I can tell, the Equipment a shop sells has nothing to do with the Agency they teach for. It's up to each shop owner to decide what equipment he wants to sell. Some do it by selling equipment they would use and recommend to their own family, others do it by how much mark-up can I get and what's my profit margin.