We had a rather poor experience on a previous NCL cruise to Bermuda, so we were a bit skeptical about this cruise. However, NCL is the only cruise line that does an exclusive Hawaii itinerary, so we decided to do it. We were very pleased with the result. The ship had been refurbished this spring and was just lovely. The staterooms were a bit small (we had a balcony cabin and it was quite small), but everything was clean and better than we expected. The main dining room food varied from average to excellent. We'd recommend eating at the Moderno restaurant one night - It's well worth the $20 charge.
Generally speaking, the service was excellent. In fact, there were only two crew members who were grouchy and/or unfriendly the entire week - one was a cook making omlettes in the buffet and the other was the Maitre d' in the Liberty dining room.
As always, the shore excursions are way overpriced, so book ahead online with private operators for big savings. Also, Enterprise car rental has the best cars and service on all of the Islands. You can really save a lot if you rent a car with another couple.
Overall, we highly recommend this cruise.