A good friend of mine is an instructor with Island Scuba over there at the Maui Ocean Club.
I went out and tagged along on a drift dive at Black Rock (big rock between the Sheraton and Marriot)......I "think" it's the Sheraton, while my buddy took some people out on discover scuba. I just kind of "tootled" around with my video camera and had a blast with the friendliest turtle I've ever seen. He followed me and did nothing but, pose for the camera. Actually, I think he wanted a hand out from me.
Island Scuba will shuttle you next door, to the Sheraton, you'll don your gear, get into the water and drift over to the Marriot. Great night dives there too! Without looking at my log book, it's no more than 40 feet around the reef there. When you get closer to the Marriot, make sure to look up or you might give a snorkeler a piggy back ride.
If you talk to Island Scuba, you'll most likely go out with Vic. If you see Vic, tell him that I recommended that you come see him. Since I don't normally put my full name out on forums, just mention Lori the stunt woman.
If your up for some boat dives and if you like a 6 pack boat, (they can take I think 10 people but, they don't) I can also recommend Prodiver Maui, based out of Kihei boat ramp. Very personable service and safe op. I always seem to leave that boat with a smile on my face
and always go back. It must be the hot chocolate Captain Don makes for me when I get back on the boat from a dive
Have fun on your trip!