Booked this trip to see and navigate Cape Horn. Stopping at the Falklands was an added bonus and the best part of the trip. Embarkation experience was somewhat stressful. Clearing immigration in Buenos Aires took about two hours (not Viking's responsibility though) due to long lines. After that, someone had picked up my wife's suitcase by mistake. Fortunately it was another Viking cruiser and it all worked out but did cause a lot of angst. Getting to the Viking staging area to the bus was somewhat chaotic. They stopped you in the middle of a busy terminal to further direct you to another line for luggage drop off to yet another line for bus transportation.
The ship was new (in service Spring 2019) and clean. No complaints there. Included shore excursions were ok but generally a lot of bus riding. In Montevideo, time allowed us to purchase another excursion advertising the tango dance. Most the trip was revisiting what the included tour did in the morning and the tango dancing was at a bar with limited stage and seating facilities. The dancers were excellent though. The best tango exhibit occurred on ship in Argentina when a dance troupe (Junior Cervila) came on board- absolutely fantastic. In the Falklands, we added the Bluff Cove excursion to see penguins and was well worthwhile and significantly shorter than a full day excursion that did essentially the same at a different location. Included excursion at Puerto Madryn was a very long bus ride to a Welch Tea House. The tea service was very nice: but for me, not worth the long bus ride.
Fortunately we had great weather for the Cape Horn segment, from what I hear, most people are not so lucky.
Cabin was excellent. If you are susceptible to motion sickness, not recommended though, due to being high in the ship.