It is well known that Celebrity Constellation is one of the older vessels in the Celebrity fleet, but considering she is about to go in for a significant upgrade in May 2020 in France, she is in pretty good nick.
Sure, you always notice minor things like a bit of rust or flaking paintwork on the outer hull structure, which had no detrimental effect on my enjoyment of the cruise, but otherwise they keep her well maintained, particularly inside the vessel.
The friendliness and service level of the crew in the main were very good. You will always come across the odd bar or wait person who is having a bad day and is a little curt/short of a smile, but arent we all on occasions? Again, it did not deter from the enjoyment of the cruise.