We were on the Crown (late Jan) from Santiago to Buenos Aires. Evaluating the cruise is difficult because we were among the large number of passengers struck by "the bug". We were out of action for two days of the cruise and not full strength for a few more days.
Cruise Pros were: Great room steward, low key, everything got done with no fuss, bother or need to follow up. Wonderful itinerary. Physical improvements to ship with transfer from Orient Lines are impressive (particularly the spa/gym areas and, if you have children, the facilities for them). Specialty restaurants were generally well liked. Excursion and main desk services were provided with smiles and helpful answers.
Cruise Cons were: Food/service in the buffet poor (particularly when compared to the ship when with Orient lines) -- we had to stand in a separate line for a glass of water (ridiculous!) -- servers stood in the same line area as the passengers struggling to get by. Note: So many people complained about the buffet that we were told (maybe just gossip) that the food service director held a meeting to sort out what could be immediately improved. I have got to believe they have tried to change this for the better. Entertainment was fair to poor -- one act (juggler/comic) was particularly crude (and I like off color jokes so offending me was surprising). Food/service in the main dining room was inconsistent -- service changed dramatically for the better the last two nights in anticipation of comment cards. The clinic nurse was particularly poorly trained re customer relations.
Pre/Post Cruise Pros: Buenos Aires Sheraton was very, very nice. Buenos Aires was fun to visit. Restaurants were particularly attractive at prices well below those at home. The locals were very proud (for good reason!). Shopping on Florida Street was ok -- in the departure line at the airport we were told we should have been shopping in the area near the cemetery where Eva Peron is found.
Pre/Post Cruise Cons: Santiago Sheraton was a mixed bag -- great four star public facilities with Motel 6 rooms -- couldn't figure that out! Santiago was ok but not a lot of fun. In both locations the tours purchased from the NCL host contractor required cash dollars (no credit cards) while, of course, if you booked via the hotel or other source credit cards were accepted.
I would recommend you consider booking on a newer NCL ship with a better recent track record.
DesertSailor