Each of these three lines has its own niche. From my experiences, outdoorsy Windstar draws passengers more active and sailor-casual, while guests tend to be more excursion-oriented and intellectual on Azamara, where dinner is accompanied by a harpist. All three, with rates usually $200-$300 per night per person, operate somewhat below the luxury level (such as ships operated by Silversea, Crystal, Regent Seven Seas and Seabourn), at rates sometimes substantially below the luxury level.

Don’t try to compare rates, however, without considering what is included in the overall price. Some of the upper premium and luxury cruise lines include all alcohol in their rates, some include beer and wine, and others throw in the cost of shore excursions, special nights ashore, staff gratuities, airfare or, on competitive routes, shipboard credits for shops and activities.

Confused? These differences are reasons enough to consult with a travel agent to book a premium or luxury line. Otherwise, be prepared to spend hours on research, with a calculator.

Which brings us back to the sushi, the lobster and the lamb chops aboard Oceania’s Riviera.

“As long as you put lobster and caviar on the menu, with a glass of champagne, everybody is happy,” said Christophe Belin, Riviera’s senior executive chef. “Our food and food service are well in competition with luxury lines, with no charge for the specialty restaurants. But we are not luxury. We are like an exclusive country club.”

Sisters Riviera and Marina are roomy ships. My Caribbean cruise was full, but that never was obvious. Deck chair areas and indoor lounges were not crowded. In the dining rooms, from the Grand Dining Room to the outdoor café, there was always an empty table, unless you wanted an extra evening at one of the four fine specialty restaurants in prime time. Every passenger is guaranteed a set number of specialty restaurant reservations, depending on the length of the voyage, at Red Ginger (Asian), Polo (steakhouse), Toscana (Italian) and Jacques Pepin’s French bistro called Jacques.

I tasted escargot, French onion soup, lobster thermidor, curried chicken in coconut milk, foie gras, duck breast, Kobe beef burgers, steaks, veal chop, king crab, shrimp, papaya, sushi, tuna, sea bass, Maine and Caribbean lobster tails, salads, fruit, cheeses and a few desserts.

Oceania has managed to make its Terrace Café a dinner favorite. The self-serve, food station restaurant, high at the aft end of the ship, is well staffed and has tables inside and out. They drew a regular group of casual diners who filled a series of small plates from a substantial array of choices that included a raw bar, sushi and cheese counters, and a grill that never ran out of lobster tails or lamb chops.

Chefs showed up regularly in dining rooms, talking with passengers about food and presentation.

Each night, it seemed, Belin, the executive chef, was in the Terrace Café. As I passed him, he would look over the items on my plate, and I could feel his judgment. I wanted to rearrange things, so the plate looked more presentable, or stop back at one of the serving stations to add another color to the palate to please the artist on this ship of foods.

David Molyneaux writes monthly about cruising. He is editor of TheTravelMavens.com