We just got back from THE VACATION OF A LIFETIME in Hawaii!!!!!!! The islands, the weather, and the ship were perfect. We would highly recommend this cruise to anyone, and we did not want it to end!!!!! Not only did we rent cars (not through ship) and drive to all the major attractions on all the islands, but as a bonus, the ship sailed by glowing lava dropping into the ocean one night and the green Napali Coastline cliffs one afternoon - both gorgeous. We watched the Napali Coast sipping drinks on our stateroom balcony. The negative reviews on the shipboard food and service proved to be totally incorrect. We had excellent sit down meals in elegant restaurants with prompt service and wonderful presentation. We liked the restaurants so much that we kept coming back (especially Skyline), and we only occasionally used the buffet, which was good, for a quick meal to get on the road. My highlight of the trip was snorkeling Molokini, Turtle Arches, Kee Beach, and Hanauma Bay. There were tons of tropical fish and big Green Turtles. I almost ran into a brilliant green Moray Eel, and I had to back off just to get a picture. My wife snorkeled twice, but her highlight was taking the submarine Atlantis down 100 ft. on the Kona coast. This is not a theme park ride - it is a real submarine - expensive but fun. To start and end the vacation, we stayed at ResortQuest Waikiki Beach (surprisingly reasonable and newly remodeled) close to Diamond Head and we had a view of Diamond Head and the ocean from our balcony. It was nice to have a day off to rest in Waikiki between the cruise and the flights. It also gave us a chance to see the excellent poolside Hawaiian show and fireworks at the Hilton Hawaiian Village on Friday night. We loved the Tiki restaurant (across from the beach - 2nd floor of our hotel) sipping Mai Tais, Blue Hawaiians and Hawaiian Ice Teas to live Hawaiian music on Waikiki beach, and we even got to see "our ship finally come in" the morning of our cruise and go out all lit-up at night after our cruise.
Some notes on car rentals and driving: the Thrifty Blue Chip membership worked out well for us. Thrifty was fairly quick and very courteous, reasonable and efficient. We had enough time off the ship to explore the major points of interest on the islands. We brought a GPS navigation system with us and it proved invaluable, but the x-ray security @ LAX wiped out all the Hawaiian addresses that I entered, and I had to re-enter them. I would not let them x-ray it after that.
From the airport to our Waikiki hotel, we took the Roberts Hawaii shuttle bus which was reasonable, and our driver gave us a wonderful free tour.