We cruised for 25 nights on the Equinox doing back to back Greek Islands, 12 nights, and Venice overnight, 13 nights. We were in the same cabin for both cruises and we did not tire of any aspect of this trip. Ship is lovely, entertainment was fine, food very good, and fellow passengers friendly. But the service far exceeded our expectations--every crew member you passed had a smile and a greeting and time to talk. When we returned from the day's excursions, the "welcome home!" felt genuine. The ports were magical, especially on the Venice overnight, the second trip. Extremely port intensive, but you get to see a lot of Europe in a short time. We booked several ship excursions--Pompeii, Ephesus, Aix-en-Provence, wine tasting in Tuscany, and olive oil tasting in Rome. All were excellent with knowledgeable guides and reasonably priced. Also booked private tours with contacts on cruise critic through Romeinlimo. Also excellent. Cabin was largest we've ever had with big shower and tons of drawer and closet space.
I have no cons at all, and I'm not so easy to please with over 20 cruises.