I have enjoyed our four cruises on Royal. We have cruise twice on Carnival, but I prefer Royal.
I have never sailed Disney and don't expect to do so. They don't have casinos on Disney and I do like to visit the casino a few times during my cruise.
Carnival Liberty New Year's Eve 2007
Liberty of the Seas 5/2008+11/2009
Allure 1/16/ 2011
Independence of the Seas 12/29/2013 Top-notch!