My wife and I booked the Celebrity Infinity round trip Buenos Aires, with visits to Ushuaia. Antarctica, Falklands, Puerto Madryn and Montevideo. We went for Aqua Class, which was terrific.
Our first problem however was the embarkation for which we arrived at 1:00PM and didn't actually board the ship until around 3PM, 2 hours of standing in lines! I think this was not primarily the ships's fault. Buenos Aires, in their love for central beaurocracy, had 3 ships loading through one medium sized building (packed) and then we were directed to wait for a shuttle bus to take us to the ship.
The ship itself was very clean and well organized, and all of the ship staff were friendly and helpful. Our aqua class room was well organized, clean and comfortable. The BLU restaurant was excellent. Meals were well prepared and healthful. seating was mostly tables for two, but each table was very close to another table for 2, so it was like a table for 4, except that you met a different couple every night. Nice! The Breakfast was also very nice for days at sea, but not usually practical for port days, because service is slow and you may miss your tour.
The itinerary on this cruise was fantastic. We had great weather, and Antarctica was one of the most beautiful places we have seen. Many seals, penguins and whales.
We had one ship problem in Puerto Madryn, where there was some delay in leaving the ship in the morning and the unloading area on deck 2 was crammed with people for almost an hour. Celebrity should have had people wait in the theater or their rooms until the problem was cleared.
Finally disembarkation was another serious problem. We, like most Americans, had a late night flight out of Buenos Aires airport, so we booked the city tour and tango show that would drop us off at the airport later in the day. This tour started at 7:30 in the morning and dropped us at the airport at 1:30PM. Apparently they were trying to accommodate some passengers who had late afternoon flights. Our flight was at 9:30PM, so we had 8 hours to kill!. Worse, the airport will not let you check in until 3 hours before the flight, so the entry area of the terminal was crammed with Americans, with limited plastic chairs and few amenities. Celebrity should have arranged a later and/or longer tour to accommodate all the people (probably most) with late night flights.