Hi europe14, welcome to Cruise-Chat! Congratulations on your up-coming cruise, what a fabulous itinerary. I haven't had the pleasure of taking that itinerary, but hopefully, there's still time to do it!
I am assuming you're talking about transfers from the port to the airport. I think the cab fare was $25. The plus with the ship transfers are your luggage. When we've taken the transfer, after clearing customs, the luggage was taken out to the bus. Not sure if that applies to all cruise lines, but with Princess it did. The plus with a cab is, you don't have to wait for everyone to fill the bus. The cost is about the same.
I've sailed on NCL 4 times and have never had problems with their service. The wait staff, cabin stewards, casino workers, crew have always been great. They're a little more laid back than other lines, but that can be a good thing. They're not always pushing for you to buy something or do something.
Please let us know how it goes! Best wishes!