I spent my birthday week on board Reflection. It's a gorgeous ship, and some aspects of the cruise were very good, but I don't think I'll sail Celebrity again. I prefer Royal Carribean and Princess.
The best thing on board was the entertainment. Production shows were comparable to West End and Broadway standards. The singers that played in lounges and bars were all truly excellent.
Our balcony cabin was spacious with a very nice bathroom. Only gripe was that there was not enough storage space for my liking.
Food onboard was a mixed bag. I found the specialty restaurants good, especially Tuscan Grill. However, in a cruising first for me, I did not like the food in the main dining room. One night I had salmon (it was awful) another night I ordered soup (it tasted like cup-a-soup). The buffet was not consistent. It was excellent at breakfast, good at lunch, OK at dinner (we had dinner there once), but very poor after 10pm. The best guilty pleasure about a cruise is going to the midnight buffet and having food before bed! All that is available on this ship is pizza, and sandwich stuff.
I took an instant dislike to the cruise director after he made what I considered to be a racist joke on the very first night. I have often complained that cruise directors are too in your face and make too many PA announcements, but on this ship it was the reverse. Apart from briefly seeing him at the end of the production shows we never saw him. I actually wondered what he did to earn his keep.
Activities on board are all very low key. This is a cruise for people who like to sunbathe by day and drink by night. There isn't much else to do.
Staff were all friendly enough (as you'd expect) but they didn't seem as genuine as the staff on Royal Caribbean.
In short, I guess I didn't like the patronizing vibe on this ship. It's like a posh nanny state that makes choices supposedly in your best interest. Anything considered "naff" is off the menu and off the activity list. To put it crudely they're a little up themselves.