The best thing about this cruise were the ports. St. Petersburg was wonderful. We took a private tour to Peterhof and the Hermitage which was wonderful. The next day we took a tour to Catherine's Palace which was a horror. The tour guide went so fast that she lost four of us. After standing on a street corner for about 25 minutes we met another group and joined them so that we could get to the restaurant where we had an awful lunch and then supposedly saw a show. Since our view of the show was blocked by a wall, we saw very little. However, the palace was wonderful. I would recommend going with either a private car or using a private tour company, not one of Carnival's group tours. Even though Carnival says you must use their tours to get off the ship without a visa, this is a lie. You can also use a tour company that is approved by the Russian Government.
We also used a private tour company in Berlin and it cost us about 1/3 of what Carnival was charging. Carnival will tell you that it takes about 4-5 hours to reach Berlin by car. Not true. It took 3 1/2 hours to get there and 2 1/2 hours to return.
Now as to the ship itself. The best thing were the cabins. They were nice and roomy and had plenty of storage space. The rest of the ship was a disaster. Imagine having to walk through the cigar smoking lounge to get to the Internet. Our dining room was opposite this lounge so when you exited, you frequently got a lung full of smoke. Also to get around the ship on certain floors, you had to walk through a dining room.