Joe,
Just got back Monday evening from Maui. Left 80 degrees and sand and returned to 20 degrees and snow. Someone remind me again why we live in Nebraska... Anyway, we stayed at Papakea, which is right next to the Embassy Vacation Resort. I dove seven of the ten days I was there. I reserved all my dives prior to leaving home for Maui.
For shore dives, I heartily recommend Shaka Doug
http://www.shakadivers.com/welcome.htm. I was the dad with the two young sons that dove with Doug the same time as Happy2Bme and her husband (who returned home to much less snow, thank-you-very-much). Had a great experience and my 12 and 14 year old both got certified on the trip. Doug responded quickly to emails and was easy to get ahold of on the phone. I really appreciated his flexibiilty with dive times (we were there with extended family and had other "obligations" on one of our dive days). We got a CD from Doug after the dives which had GREAT pics and video of our dives. It has been a big hit back home! Especially while waiting for my photos to be developed (still on film).
For boat dives, I can not imagine that you could find a better operator than B&B Scuba
http://www.bbscuba.com. Dove four days of two tank dives with them. We hit the backwall of Molokini three of those four days. EVERYONE, and I mean EVERYONE on the boat was terrific. Brad and Blessi (owners) were on the boat all four days with Blessi leading most of the dives. Bill was the boat captain and did a great job. Stan the DM was a great help. Can't say enough good things about them. I drove from Papakea every morning at 0500, arrived around 0540 (not much traffic that early if you can imagine) and was back home by 1100 all four days. One of the reasons I chose B&B is because of the small boat (max 12 divers) and the early departure and return times. It worked out really well because by the time I returned in the morning, my wife and sons had slept in late, eaten breakfast, played on the beach and/or pool, and were ready to go do something fun when I returned.
Finally, I also dove the Maui Ocean Center Shark Dive
http://www.mauioceancenter.com/NewsandCalendar/PressKit/SharkDive.html. Another terrific experience. On the day I dove, it was just me and the curator, Jeff. We had a 40 minute dive in the tank and hopefully got some great pics. They let you keep any shark teeth that you find in the gravel and I was fortunate enough to find a Tiger Shark tooth. Both Jeff and Ray (another diver/curator who attended to my family while I was on the dive) were jealous, saying it was the largest Tiger Shark tooth that had been found in the tank at that point. A bit expensive, but very enjoyable.
All in all a great trip with some great diving. Looking forward to diving Maui again to hit the Cathedrals and get in a night dive or two. Would go with Shaka Doug and B&B Scuba without hesitation. If you have any other questions, don't hesitate to pm me.
Steve