Jack,
Sorry the reply took so long. I haven't checked the site in a few weeks.
Concerning the Tahiti Aggressor. I cannot say enough good things about the boat itself and the crew. About the hardest working crew I have seen and very safety conscious.
I think the diving itself is very unique with regard to other destinations in that it is VERY weather and "conditions" dependent. In most other places, there is usually somewhere decent to dive if weather, etc is not cooperating (ie, leeward side of island). At all the atolls, there is essentially only 3 dive sites. 1.) the pass itself 2.) the left corner of the pass 3.) the right corner of the pass. Of course the purpose of going on the Aggressor is to dive the swift currents through the passes during the incoming tide. So, the ideal day would be two pass dives a day and two corner dives. BUT... if the conditions are not cooperating you may be diving the same sites throughout the day (the two sides of the passes are not very different).
On the week that we were there (May 17-24) there was a southern swell that was "washing into" the atolls, effectively filling them (think of the atolls as a bowl with all the passes on the northern sides) consederably decreasing the currents through the passes. We were only able to make one pass dive per day always in the afternoon (about 4pm) and the current was only 3-4 knots. The am incoming current was almost non-existant. Therefore the other dives were on the corners.
Because of bad weather, we also spent an extra day diving Rangiroa (2 1/2 days total). Again, due to a storm, we dove the checkout dive site (aquarium) 3 times which everyone thought was boring. I liked it because there was plentiful macro subjects for good pics (see attachment). On our last day, the captain wasn't sure if they were going to make it out of Rangiroa at all the following week.
Even with good conditions, I thought the variety of life was limited compared to other places (fiji, hawaii, etc). We specifically went there to see sharks and it did deliver.
Also, very plentiful and tame turtles in Rangiroa. Almost no small nudibranchs (tree types of flat worms we saw), crustaceans to speak of. I'm happy I went. We had a good trip, but I wouldn't do it again.
As for perspective, I've done a liveaboard in Fiji (Fiji Aggressor) and the BVIs and land based diving in Sea of Cortez, Hawaiian Islands, Belize, Cozumel, Grand Cayman, Bahamas, Barbados, Antigua, Jamaica, and dive at home in Southern California.
Hope this helps,
John