Having been on MSC for 3 cruises since 2005, (Opera, Opera, Lyrica) and scheduled to sail on the Poesia in November, I have never had a bad experience on any of the cruises. I will say they have not been in Europe but I loved the food, pizza, and entertainment. It is not mass market cuise line entertainment but it is well done. I have always been amazed with the ability of the cabin staff to always have the cabin clean and never be seen. They have a wonderful system using door tags.
I would probebly never take an MSC cruise in Europe because it is just to different from what I expect. I don't like paying for water at dinner or starting dinner after 9PM. But that just the European way of the world.
You have to like being a minority on the cruise but the Italians sailing with you will always cheer you up with laughter and song and if you like beer with breakfast there are always the humorless Germans. Yes, you have to accept that the Germans will just jump ahead of you in the buffet line but that is just their culture.
The only issue we have ever had was leaving from near the north parking garage in Port Everglades and returning near the south one. Had to take a shuttle. Carnival did the same thing but in reverse last year so it is just a function of port spaces and probably bad planning by the port authorities.
So give it a try but go in open minded and think that you are eating and living in Europe for 7,10, or 12 days.