Not to hijack the thread, well maybe just a bit... What do you intend to do with your certifications? I mean, what is your end game, your goal, your raison de le faire as it were?
Some people just want certs to collect cards. While many poo-poo this, I find nothing intrinsically wrong with this approach. If that is the case, then the more cards, the merrier and all that matters is if you have fun!
Some people see this as a natural progression to their diving. Again, not a bad reason at all and it shows your commitment to diving and that the marketing machines are operating. Following the stepping stones to a bigger achievement is never a bad way to go.
A few really want to become better at the craft of diving. Right or wrong, this is celebrated by our community. If this is the case then the choice of instructor is more important than the shop or even agency. As RJP showed us, plinking off the requirements for each course is pretty simple and they are all pretty similar even from agency to agency. After all, AOW is required by many dive ops to do the deeper or more challenging dives like the Speigel Grove here in the Keys. But what are you really getting for your time and money? Every instructor is different and not every instructor will fit your personality or honor your goals. It's up to you to decide what you want in an instructor and that again, depends on your overall goals. Then you need to ask the shop/instructor and see if you think it's a good fit. What is the instructor's emphasis or do they even have one? Has anyone talked about them here on SB good or bad? Do any of your friends or the divers you respect have a recommendation? What is their gear like and does that even matter to you? I'm sure there are a number of other questions you can ask. Just remember, you can call a class or instructor just like you can call a dive. If you're not having fun then walk away and find someone else. Classes should be fun and challenging. If you complete a class wondering what, if anything you got out of it, find a different instructor for the next one.