I did my AOW in Coz with Aldora Divers.
Best I remember I had to read 2 chapters and turn in the Review Question pages each day.
Navigation was challenging for me. My instructor had me do my navigation check -out dives during a night dive. I guess he figured if I could do it then I could do it any time.
For my deep dive we were at Columbia Deep at 132 ft. he had me do some skills to show the effects of nitrogen at depth.
Other dives were pretty routine, but good experience.
Doing AOW in a place like Coz. could give you a false sense of accomplishment though. By definition you are certified for conditions equal to or better than those you were certified in. It don't get much better than Coz.
I've done some low-viz and zero-viz stuff for rescue and recovery dives for our local Fire Dept. My AOW didn't really prepare me for those, but I don't know if anything could.
I am a proponent of always striving to better one's training and skills, though.
Good Luck,
Todd