We just recently came back from our cruise on the Explorer of the Seas to the Western Caribbean. This was our first cruise so I am unable to make comparisons. We've been to the Caribbean before but have always stayed at resorts. I'll try to give a lot of details.
We flew down to Miami on Saturday and stayed at the Courtyard Marriott in South Beach. They offer a Pre & Post Cruise package which included a shuttle to the port on Sunday and buffet breakfast. It was nicely located just 2 blocks from the famous Lincoln Road pedestrian shopping area and 3 blocks from the beach.
We left the hotel for the port at noon on Sunday and were surprised to already find a ton of people there (we thought we were getting there too early!). The porters were waiting outside and took our bags. We then went and stood in line which took a little over an hour to get through. Once we boarded the ship we were told to go help ourselves to lunch at the Windjammer Cafe (their buffet restaurant). It was crowded as this was the only restaurant open at that time. However, it is not like that the whole week. We were able to immediately go to our rooms and our bags showed up a few hours later.