Oceania, Marina, does a very nice job. Embarkation was as smooth as could be. The ship and staterooms are beautiful and very comfortable, staff amazingly attentive and the food terrific. We especially liked the specialty restaurants we went to, Jacques and Toscana. They and the other specialty restaurants require reservations which are not always easy to get, particularly based on the category of stateroom, but the Grand Dining Room is lovely, never crowded. In fact, a very pleasant part of the experience was the feeling that the ship never had crowds, even though it was fully booked. Dining is the primary evening activity, don't go for glitzy shows as there aren't any, which suits the passengers just fine.
One hint for the passengers willing to go outside a comfort zone just a little. The shore excursions run by Oceania are very expensive compared to land based tour operators, Alla and SPB travel. We booked with Alla and were thrilled with the smaller groups, much smaller price (by at least 50%) and the very knowledgeable guides in every destination. You may have to walk a few more steps in a port to get to their van, but when there are six of you with one guide as compared to a group of 30 or so on an Oceania tour, you will know you made a good choice. No fear ever that we would miss the boat, the companies are way too professional to let that happen, although that concern was expressed by others on board.