We are somewhat experienced cruisers - this was our fourth. Previous cruises were with Holland and Royal Caribbean.
First off, the up sides - the itinerary is unique due to this being a US-based ship. Four islands in seven days, it is as you would expect not quite enough time in any of them, but we used this cruise as our first visit to Hawai'i to get a feel for the different islands, and it certainly did that. The available shore excursions had a nice mix of activity levels.
Unfortunately, that's where the good parts end. The level of service on-board this ship is quite a bit below those other two lines - whether it's the cruise line in general, this ship, the all-US staff, or just a bad experience this time around we can't say. Staff aren't near the level of other lines - our state room was dirty (hairs in the shower and drawers, dirt and dust everywhere).
The room (and the ship as a whole) could use a week or two in dock to fix all the minor problems. Our bathroom had rusted out seals around the door, and the water from the shower was both weak and dangerously inconsistent in temperature - it literally swung from scolding to freezing back to scolding within a few seconds, constantly throughout the cruise. They do a little CYA with "Test water temperature" signs everywhere, but again, since it is so variable, that doesn't help. The balcony was cruddy with buildup, despite them trying to wash it at 3am one night.
The emergency procedures were laughable. Our assigned emergency location was "M6". M showed on two places on the maps (without numbers) - on deck 5 and deck 6. If you thought M6 meant the M on deck 6, you'd be wrong - it's in the back corner of the restaurant on deck 5 - something that is labelled or mentioned no where except the overhead announcements prior to the drill - even two crew members we asked didn't know. If you board after the drill or otherwise miss the announcements.... good luck. This location was also not terribly close to any of the lifeboats we could see - if something catastrophic did happen at sea, there would be a great deal of chaos.
Dining room staff were very inexperienced and harried - our first night we were led all the way around the main dining room by the staff member looking for our table. Service was very harried and very nearly rude - .more than once plates were dropped off at our table and the server just kept walking. We waited around 30 minutes between ordering dessert and it arriving (partially melted - it had been sitting out somewhere for a while).
The upcharge restaurants were somewhat better. Teppenyaki was enjoyable, and Cagney's was passable, but more around the level of the typical dining rooms on other ships.
Cadillac Diner was usually a mess service-wise as well - our order got lost once (although the manager at the time hit it out of the park with making up for that), and slow the rest of the times.
Alcoholic drinks onboard seemed weak regardless of what bar we tried.
Organization, both in terms of the check-in, disembarking, and shore excursion procedures, was sorely lacking - many times you're left to figure out where you're supposed to be at or where to go on your own, or there is one person trying to help hundreds of guests.
The Spa was, in the tradition of all cruise lines it seems, over priced and so-so in service. There wasn't a high-pressure sales pitch of creams and such afterwards, which was a good thing.
Overall, it is a cruise that you won't be spending much time on ship - and that's a good thing. The Hawai'i islands are beautiful - get out and enjoy them!