I chose NAUI originally because it required more of me.
I stayed with NAUI becuase as an Instructor I am free to alter and make the course my own as long as it meets or exceeds the standards. I could make the course as "hard" or "soft" as I wanted to.
I can spend extra time on any subject I feel is important to me and include it in the Course itself, the confined water, or open water. I'm not confined by NAUI to only do "this"....which is what another Agency does....
My courses are my courses. I want the divers to know more than the minium, I want them to do more than the minium, and I hope they want the same thing.
Diving and teaching to dive is more than the minimums and knowledge is power.
NAUI Open Water, Advanced Diver, Rescue, Master Diver and you'll know just about everything from a recreational standpoint of a solid foundation in both knowledge and skills.
I also know and understand that ALL AGENCIES have great, average and so-so instructors.
That aside, it was the actual curriculum that finally made me chose NAUI in 4 courses versus a dozen other courses to get the same information thru other agency(s). It was just more challenging.
Long winded...but NAUI.