My husband and I just returned from the 5 night caribbean cruise on the NCL Spirit. We had a GREAT time and it's a beautiful ship. We didn't have any problems at all in regard to waiting lines for dinner. We waited 5 minutes tops at all the restaurants. We chose not to eat at the buffet at all. I would recommend The Garden Room for dinners, it's free and has very good food. We went to the Bistro and it was so-so for $30.
The only complaint we had and will write to them about was our stateroom #11536 was directly below the Gym AND the TREADMILL!! You would not believe the noise! We had no problem with it during the day or early evening but the Gym is open 24 hours and when people got on the treadmill at 3am we knew it! I really think they should curb their hours, maybe close at 11pm.
All in all it was a fantastic trip and our first time on NCL and we would definately go NCL next time.
Hope I helped someone who is sailing on NCL.