Dive Oahu has a good deal on a 5 day package. $385 for five days and anytime the boat goes out you can pretty much be on it. I did 3 or 4 a day a couple of weeks ago. They work out of Fishermans Wharf in Waikiki. Ocean Concepts out of Wainai (not sure about the spelling) does some interesting sites for $100 for two tanks on their boat. Very different cultures at the two shops. Ocean Concepts, pure professional relationship. Dive Oahu treats you like family. Depends on what you`re looking for. I`m planning a review of the two as a blog but I haven`t finished proofing it yet.