Our cabin was in the back of the boat. It literally felt like there was a freight train at times in our cabin. It was rocking so bad that we had to put towels around the lock safe because of the banging noise. My fiance had been on other cruises and had never felt anything like it. It was my first cruise so thank God I used the wrist bands and did not get sick. It wasn't just the back of the boat however. People were complaining all over. Even the pools needed to be emptied at times. (btw-pools were very small).
And the seas were not rough at all.
As for the food. It was just ok. I was very disappointed because I had heard the food was awesome on cruise ships. I would have rather eaten at the buffet or the pizza shop rather than the fine dining room.
Loved the Serenity for adults. When you aren't traveling with children it is rather nice to get away when you just want to relax.