My wife and I are fortunate to cruise every year for the past 10 years, sometimes twice a year. We have also tried 5 different cruise lines. By far, we feel that Celebrity delivers the best value for the dollar.
The Constellation is our third Celebrity ship, having been on the Zenith and Millennium before. Hands down this was the best ship in terms of food, service, entertainment and overall experience we have ever been on. A friend of ours who traveled with us (her first time on Celebrity) was enthralled with the cruise.
The crew hustled and all of them were very friendly. You know, it's a given that the entertainment staff, housekeeping and servers will be friendly. But we found the manual labors cleaning the ship and pool people went out of their way to be polite and accommodating. We have never seen that on any ship, ever.