I stayed in a balcony cabin on deck 8. The ship is beautiful and the cabin was great. The stateroom staff came twice a day to clean and switch towels, and provided a great service. Breakfast and lunch buffet was fine, but the food at dinner was overall disappointing. Smoking is for some reason allowed in many common areas, so be prepared to hold your breath while passing some areas. Especially I find it strange that people can smoke in the pool areas where there are children and you would like to relax.
I you book excursions prepare to wait 30-45 minutes in the theatre. Excursions seemed to be poor coordinated which caused long waiting time. As a result many small children lost their patience and cried (understandable).
Tips are extremely high on this cruise compared to other companies. Each person are being charged USD 12 per day which is USD 168 for the entire cruise. Put in mind that you also have to pay a service charge of 15% each time you purchase anything from bars or restaurants. I guess that MSC does not pay any salary to their employees.
Balcony cabins can have restricted sea view due to life boats.