Cruise in Brazilian waters: Royal Caribbean, MSC or Pullmantur?

[Fattony]

My wife wants to take her parents (Brazilian) on a week-long cruise out of Rio. Choices are Royal Caribbean (Splendour of the Seas), MSC Orchestra and various ships on Pullmantur (Spanish cruise line). Travel agent in Brazil says the Splendour of the Seas is small and outdated, and the Pullmantur ships only so-so at best. He talked up MSC ships (mostly ships other than the Orchestra), but the reviews here of most MSC ships are not very positive. The few reviews of the Orchestra I found weren't that good, either. I did find reviews of the Splendour of the Seas here, but none of Pullmantur.

 

The MSC Orchestra is larger and newer than the other options. MSC has a brand new ship that just started service last month, but it won't serve Rio, and since her parents are elderly, and the mother, at least, needs a wheelchair, she'd rather not fly out of Santos. My wife really likes Princess ships, but they only serve Brazil as part of much longer cruises (e.g., 14 nights to Valparaiso), which would be too much for her parents.

 

Ideas?