We chose to go on the Symphony after having sailed on the Allure seven years ago. We have been on other ships from other lines in between, but we loved the size and variety on the Oasis class ships. We knew that we would be paying a premium to sail Royal's newest ship in the fleet, but we thought it was worth it, having sailed on the Allure in similar circumstances.
I have found that most of the other reviews people have left are fairly accurate. Embarkation was very smooth, especially after having done everything online. I did find that during the days leading up to the cruise, the RCL website was somewhat buggy and I had a few problems logging in to upload photos and fill out the information. I also sometimes had problems with the cruise planner on their website for dining/entertainment reservations.
Disembarkation was just as smooth, with the grouping system being used to get people off in an orderly fashion. My one complaint is the ground transfers that we purchased through RCL to get us back to the airport. Once you are off to the ship, it is chaos and hard to find where you are supposed to go. Even once you get to the buses, it is chaotic and nobody really seemed to know what was going on. People were getting onto the wrong buses and then having to get off. They could use some more order for that process.
The room itself was very large and included one king bed, a couch that converted into two small twin beds, and a curtained off nook with bunk beds. Our favorite feature of the entire room was the giant walk-in closet that had ample shelving and space to hang clothes. The bathroom was small. In a room designed to hold 6 people, it would be nice if they did the Disney ship style bathrooms and put the toilet and shower into two separate rooms. I was a little surprised to see the condition of our stateroom, it looked a little beat up for being less than a year old. Large stains were on the carpet and the paint on the windows in the room was already all scratched and worn off.
The port in Nassau was very crowded, with 6 or 7 different ships docked there as well. The port area itself seemed fairly run down and dirty. I was somewhat surprised, as I would have thought the port would have been the nicest of the ones we visited, but it was the most dingy and run down.
Cozumel has a large amount of shopping right in port. However, with 5 or 6 other ships docked, it felt pretty crowded.
I liked that Roatan had shopping so close to the ship. You basically walked off the gangway and hit the shops. There wasn't a huge amount of variety, but you had your choice of souvenir shops.