DH and cruised on them because of their great price in 2009. Before I went I did all my research on Cruise Critic and frankly was rather worried. There were a lot of negative reviews. But we absolutely loved it and had a wonderful time. It is different from the other lines. They don't schedule round the clock activities. Most of the officers and crew speak English as a 2nd or 3rd language so it may not be as easy to communicate (but we had no problems).
The shows were wonderful. They do the announcements in several different languages (something else that CC complained about). There were a large number of Europeans on the ship, something that was also a complaint. I have no idea why that was a problem.
Lots of complaints about the food but we didn't find one thing we didn't like. If your idea of the best Italian food in the world is Olive Garden then you may not like it. We aren't foodies, but we also appreciate well cooked, unfussy food and loved it all. Food may not be available 24 hours a day-- they may close the buffet for an hour or so --horrors! CC posters were apparently starving to death during that time.
I haven't checked the CC boards lately so hopefully the opinion there has changed. When I sailed was I think their 2nd year out of an American port so there were a few wrinkles they were ironing out but I can't think of one thing we didn't love on our cruise. Without endless activities we were able to relax and enjoy our ports and our time together. I did talk to a few Teens that were pretty bored with the teen clubs, not much going on or supervision so if you have kids that age that could be a problem. But the younger kids seemed to be enjoying it. We did hear complaints on our cruise but they were from those expecting a Carnival or
Royal Caribbean style cruise, which is not MSC's style.
Hmm, maybe I should go see what they have available. With a great deal (do they still have kids sail free?) I might be able to convince DH.