We have sailed over 20 times on large ships, small ships and river cruises. This was our third Celebrity cruise although our last one was several years ago. The main point of this review is to advise fellow cruisers to not choose Concierge Class with Celebrity. I believe you will find as we did that the added price brings either a) services not needed or b) services not delivered. Bottom line, go with a Suite so you get better dining options or save your money and go one class down from Concierge.
Celebrity did have a separate line for check in for C Class but given the relatively smooth boarding process and the fact that everyone had to wait until 1:30 when all rooms were made available for use it mattered little. On disembarkation we did have a separate area to wait as promised but there was no added time advantage to C Class. We left the ship with everyone else who had similar flight times so no added benefit here either. Daily snacks were promised but we enjoyed them only twice in 12 days since you had to be in your cabin when they come by and your cabin steward has to remember to leave the form. We did have fresh fruit as promised which consisted of one pear, one apple and one orange which is not exactly a robust benefit. We did receive a bottle of champagne but the promised early deliver of luggage was a bust. So, avoid C Class.
As to the rest of the experience:
Cabin was fine but balconys privacy was compromised by the odd shape. No plugs by bed and inadequate plugs for charging personal devices.
Did not take an excursion as we had been to Amsterdam before. Just flew in from the U.S overnight and boarded the ship.