Me and my partner chose to cruise with celebrity after enjoying a fantastic cruise on the Royal Caribbean Explorer of the Seas 2 years prior.
We thought since the two are related and celebrity is more expensive that the experience should be even more fantastic. I have to say, we had a better time on the Explorer.
Not sure whether this is because of the people on the ship... we are 25 but we don't drink and aren't party animals - But wow, this is a very sloooow crowd and the daily planner reflects that. There is literally nothing to do during the day other than go to talks where they try to sell you things.