Oceania Sirena receives high praise for its attentive service, excellent food, and intimate small-ship atmosphere. Guests consistently highlight the quality of the staff, the well-maintained cabins, and the diverse itineraries. However, some reviews note areas for improvement, such as inconsistent service in certain venues, limited dining hours, expensive and sometimes underwhelming excursions, slow internet, and occasional issues with port changes or communication. Entertainment is generally enjoyed, though some find it lacking compared to larger ships. Overall, the Sirena offers a refined, relaxing cruise experience with a few operational hiccups.