When I initially posed this question I was simply trying to get a gauge on quality of materials that each agency offered. I have had more education that I care to think about and I know I am the kind of person that likes to have a reference in addition to having excellent in person instruction. I also think that I need a lot less lecture If I can teach myself--I for once think focus on actual skills should be a certification agencies primary goal not theory, which can be read and understood.
Numerous responses to my initial post involved explaining that the instructor makes or breaks a class. I believe that i the absolute truth. However, how can anyone possibly guarantee that they are getting a great education. Recommendations flow on SB and everywhere else that say, speak with your instructor or look for experience--what agency you go with doesn't matter. I wish someone would explain to me how I was supposed to find the most qualified instructor around when I was 17. The concept that I should have shopped around in Northern NJ without the internet to find the most concerned, experienced, and caring instructor is preposterous! That, inherently, is why agency expectations, materialized through educational materials, is such a critical discussion. Sure, NAUI vs PADI vs SDI is doesn't mean much, but you can see an agencies philosophy in the way they write their textbooks, in the way they build their certification requirements, and the expectations for minimum certification. At some point it is impossible to find the "best instructor" for you--often times by the time you know, its too late for it to make a difference until your next class.
I have both PADI and NAUI books for the basic courses, and while I like PADI for the comprehensiveness (def cover topics that they dont in NAUI), NAUI feels much more appropriate for the maturity level that should be required for someone leaving the surface where air is plentiful. Not that I dont think everyone should be certified, I am just a little disappointed that I can't grab any certified individual as a buddy--I just can't trust that everyone has the same viewpoints and mature approach to the serious side of diving.
I have read all GUE books, and despite editing issues, they are far more in-depth and focus a great deal on physics and skills, which should hint at the philosophy of the agency. I am a little saddened by their lack of fully explaining how to do everything (i like NAUIs treatment of EANx and I am not sure I would have really gotten what I would need out of GUEs books), but overall I agree with TSandM regarding their open water manual winning "hands-down." I mean, they even cover PFOs, which i haven't been able to find mentioned in any of my NAUI or PADI manuals. GUE's comprehensiveness is refreshing to see though; sadly I had never heard about buoyancy and trim until I read the book. Why is that? Were my instructors bad? Perhaps I would have been better served by a book that would have stressed it, so I would know to ask.
I have yet to see any TDI or IANTD manuals, but I am interested. Also, I just recently learned about PASI, and I would be interested in learning more about that as well.
I know I might get flak for this post, but I really dont care about the agency. They are just letters. I want to know where I go wont hold punches. I want to learn everything, learn how to execute every skill as well as possible, learn how to help my fellow divers in any contingency, learn just as much about what my limits are as I do about what I can do, and most of all know that everyone was certified that way so that the only thing holding me back from diving with anyone as a buddy are simple personality conflicts.