My husband and I have only sailed on small "boutique" boats prior to this trip. By comparison the Oceania's 700 or so passengers was large. Friends who cruise often had told us about this cruise line and praised it so off we went. We were not disappointed. the boat is well managed and maintained. The strongest plus is the international and ultra warm staff. They are well trained and up to the task of making you feel at home.
The food in both the main dining room and the two specialty restaurants compares favorably with any top New York restaurant and the Open Seating policy is a great way to meet other people if you are so inclined. For our sailing most of those traveling were couples - from 40 - 80 with the majority in the 60+ range. Predominantly American with a smattering of British and Canadian. Many had cruised on more expensive lines (Crystal, Seabourn' said that this ship compared favorably.
A word of warning - if you like glitzy entertainment and lots of on board organized activities this is not the boat for you.
The major fault we found was with the excursion desk. If you took the cruise tours each day - no problem. We took one and were pleased with it but doing multiple tours doubles the price of the cruise itself and you get so much more local color going off in a small group or on your own. The negative is if you are "independent". Each port has a tour agent that comes on board to help you arrange your day. These people are very knowledgeable but only come on board or are available once the ship has docked. The staff at the itineraries desk provides meager information so, unless you've really done your homework, this can be very disconcerting. The ship does provide a loop DVD and dailytaped itinerary briefing but it might be better to have a daily in person port of call seminar. You are always conscious of arranging your day so that the boat doesn't sail without you (and they will). Overall our experience was a wonderful one - we would definitely sail with this cruise line again