I guess I am going against the majority here. I have been to Disney at least 25 times, and also have been on the Disney 3 and 4 day cruises several times. Last month, I was on my first Carnival Cruise to Cozumel and the Grand Cayman Islands for my father in laws wedding with my husband and three children (7, 13, & 15).
We thought the food on Carnival was terrible, and we would only rate the food on the Disney cruises as a little above mediocre. But, there were many entre's and and desserts that I just couldn't eat at all on our Carnival cruise (at least I didn't gain weight on this cruise). The kids camps' were a joke as they were closed many hours thoughout the day, and other times required a family member to be present. We are not ones to actually send our kids to camps for long periods of time, but when they asked to go, we could barely find things on the schedule that they would have the slightest interest in attending. Also, the actual facilities were a complete joke in that they were small with very little to do. Some of the "organized" teen activities actually indicated "no supervision" which I don't consider something I would want my teenagers to attend.
The evening entertainment was not something that a family would enjoy together (as much of it was not family oriented). We struggled to find things to do together as a family and the entertainment we did attend together was average at best, while entertainment on a
Disney Cruise was always their best asset.
Honestly, I will absolutely never do a Carnival Cruise again, but to each his own. I can't compare it to other Cruise Lines other than Disney, and while it is less expensive, you certainly notice the difference in quality big time. Even the rooms are different in size and quality. There is just no comparison.
I am going to stop here. I feel fortunate that my father-in-law paid for this cruise for us to be there for his wedding, because I would be highly disappointed if I had paid for this cruise myself. Although, he even mentioned the lack of quality in many areas himself. We definitely managed to have a good time considering what we were there to celebrate! We had a much better time, though, when we got off the boat and checked into the Grand Floridain for a short stay afterwards.
Just my two cents... It appears many others have had a better experience.