We have cruised roughly 20 times on a variety of cruise lines, including Princess, Norwegian, RCCL, Celebrity, Holland America and Carnival.  No cruise ship or cruise is likely to be perfect.  The "Grand Mediterranean" itinerary on the Ruby Princess comes close, although there were occasional glitches that could be easily addressed.The ship is very tastefully decorated, spacious and easy to get around.  We had a balcony on the back of the ship on the Caribe deck.  This was a wonderful cabin affording great views, especially when leaving port.  We must have sat and looked at Naples and Mt Vesuvius for at least an hour as the ship moved out to sea.  There was an occasional odd smell wafting up from somewherenot the ship's exhaust, but more like passing a landfill quickly on the Florida turnpike. This was rarely noticable (occured outside only on the balcony) but at the same time unmistakeable when it happened. I would happily occupy the same cabin again as this was a very minor problem.The service was consistently excellent from almost everyone throughout the cruise.  Our room steward, the waiters in the dining rooms, the reception areas and the shore excursion desk were all staffed by top notch, knowledgeable and friendly people.  I asked one of them if Princess selected only the best from their other ships when they staffed the Ruby.  I was told that was not the casebut indeed the customer service was great.The only slight isssue I had was in the Vines barnot once, but twice.  It almosy seemed like I had a sign on my forehead saying "persona non grata" when I stepped into that area.  The Vines bar serves wine, tapas and sushi.  For unknown reasons, when I asked for a plate of tapas with our wine, we were not offered any choice but given a small plate of two or three tapas which was fine at the moment (other guests who seemed to have an inside "understanding" of the rules walked away with huge plates of sushi, cheese, assorted meats, etc.).  Given that there were two of us and lots of wine. I approached the sushi chef later and simply asked for some bread.  I was told to go "back to my seat" and someone would bring the bread. It never happenedeven after I asked again.  This would have been forgivable except for the hordes of children and non-paying people returning time and time again to get plates of fresh sushi and tapasfor free.  The second incident occurred one night when I stopped in to get a glass of wine as we were waiting (with a remote pager) to be seated for dinner ("anytime dining" can mean anytime they are ready for youand not the other way around).  The bartender insisted on knowing what I was going to "do" with the wine glass as he did not want it leaving the bar.  I finally told him to keep the wine and the glass since taking it into the dining room seemed to be a mortal crime.  PleaseI think anyone paying thousands of dollars for a cruise at my age (early 50's) is not trying to run off with a Reidel wine glass.  They sell them now at Target nowI'm not that impressed.  Give me a break!  I complained to the "head" bar manager who listened and assured me he would address it.  I avoided the Vines bar after that.  I probably contributed to the incident in some way so I will give the benefit of the doubt. Back to the positives, this really was a great experience.  The entertainment on board was goodespecially the comedian, Billy Vader (or something like that).  The food was very good in general except for the buffet breakfast, which was average and not as good as I recall on other Princess ships.  In contrast, both Sabatini's and the Crown Grill were absolutely superior in every way.  I was disappointed in the main dining room's attempt at Grand Marnier souffleit was more like a cold orange breakfast muffin stuffed into a dish with vanilla sauce, devoid of Grand Marnier.  In contrast, the expresso creme brulee was wonderful.  I have never before eaten dinner at the "buffet" on any shipbut we did on one evening as we were very tired.  This ended up being the "pasta buffet" night and it was excellent; in fact, it surpassed many nights in the main dining room.We are independent types as a rule, but this time the majority of shore excursions we booked were with the ship.  The notable exception was Athens.  My advice is do not plan to take the metro into Athens on your ownthe metro in Piraeus must have been a good 30-45 minute walk, at minimum, from where the ship docked.  Taxis would not take us there because it was not a long enough trip for them.  We were exhausted before we ever got to Athens, which ended up being our least favorite port.  Ephesus and Istanbul were outstanding and pleasant surprises.  Mykkonos was our second least favorite stop as there is really nothing to do there but walk around and have a beer.  The ship mentioned that we would be sailing past an active volcano, Stromboli, at 11:30 pm en route to Naples.  We sat on the balcony and watched Stromboli erupt at  least three times in about half an hour.  This was much more dramatic than what you see in Hawaiithe lava seemed to shoot straight up into the air for a good distance from the top of the volvano, although we were too far away to really photograph it.  I would highly recommend the tour that does the Amalfi Coast drive and Pompeii.  The Amalfi drive hands down beats almost any coastal road I can think ofincluding Australia's Great Ocean Road, US 1 in California and the Road to Hana on Maui (although that one may be a tie).  I have done this excursion twice (in 5 years) and was fortunate to have the same tour guide both timesKareem with Aloshi Bros.  If there is any way you can get the bus with Kareem when you do this tour, request it as he is extremely funny, entertaining and seems to be the most popular man in town wherever we stopped.  He said he has been doing the tour for 16 years.  He's the best, bar none in my opinion.  He called our tour bus group his "family" and oddly that's exactly how we felt.What can you say about Rome?  Rome is one of the great travel experiences anyone can have.  We took the Princess-booked train into Rome and did it on our own.  This was my third trip to Roime and the third time the Vatican musesum has been closed while I was there. Not a problemthere's plenty more to see and do.  There was a crazy person literally standing in Trevi Fountain shouting at the crowd which ruined that photo op, but added to the experience,  If you have already been to Florence, or even if not, consider doing something in the Tuscan countryside.  We did the tour to San Gimignano and Pisa and had a great timehighly recommended.  The village of Eze is a great excursion near Monaco.Last but not least, this cruise itinerary starts and ends in two of the most fascinating cities in EuropeVenice and Barcelona.  Venice was like a good, long, slow dream from which you hope you never wake. Forget the maps and GPS devices in Veniceyou'll be totally lost in no time no matter how many maps you bring, but you can always naviagte by the major landmarks.  By a two or three day pass on the Vaporetti (water taxis) and just explore with no agenda is my recommendation.  The same goes for Barcelona, although it is easier to follow a map there.  The Hotel Antiche Figure in Venice is close to the ship dock, but also on the Grand Canal, so a great overall location.  The MonteCarlo in Barcelona is similary strategically located at the top of Las Ramblas. Both are top-rated and well worth the Euros.I apologize for the length of this review.  Any comments are offered in the spirit of helping all the contributors on this site who have been so helpful to me in planning the best cruises.  Any criticism I offer with regard to the Ruby Princess should be heavily outweighed by all the positives.  It is a near-perfect experience and a near-perfect ship, and perhaps as a result, only the minor problems come to mind with regard to the overall experience.