I did my OW and ADV through PADI and am now taking the NAUI Master Scuba Diver Course. I've heard a lot of people say it is about the instructor and it may be. But the others in my current class were graduates of the NAUI advanced and by what they have told me the NAUI advanced was more advanced than my PADI class. Example is they did a rescue type dive as well as the other five dives. I'm basically taking a class in physics and physiology. I have a boat diver, dry suit and NITROX specialty and the Master Scuba has taught me more about those individual areas than the actual classes in those areas. Keep in mind, I would not get the specialty unless I paid for them individually. No agency is going to give it away for free. I wish that I could have taken the NAUI advanced and probably should have. I will say this to you, if you have the desire to continue going up to dive master or instructor, I would highly suggest that you try NAUI for at least the MSDC as the others offer. And I read that someone on here suggested you try different agencies throughout your diving experience and I have heard nothing to ever contradict that statement from any one who did not work at dive shop.