Yeh I think the O/W courses are about the same for Padi/ Naui/ SDI/ ACUC etc, with a good instructor being the main component to good training. It was the crash courses I was commenting on.
NAUI is a not for profit association- their standard is used by the US Navy I believe.
The differences between NAUI's standards for the basic courses are stricter and more demanding than most other brand name agencies. The difference is MUCH more noticeable as you go higher in the course hierarchy especially at the Master Diver and leadership levels (DM, AI, Instructor, etc.).
NAUI is a democratic not-for-profit association that is owned by its members, NAUI Instructors. The training standards are set by NAUI's Training Department who reports to NAUI's President who reports to NAUI Board of Directors (BoD). NAUI BoD is elected by NAUI Active/Sustaining Instructors. NAUI has NO affiliation or association directly or indirectly with the US Navy.