We just did a cruise on Paradise to Cuba in Feb. We chose to go with the walking tour/Spanish Fort visit thru Carnival.
It was our first time there and we were uncomfortable with all the rules/regs that were posted on CC. We had a great time. Carnivals excursion is pricey but we felt well worth the money. We had the walking tour of Old Havana, then on an air conditioned bus to the fort across the bay. We came back to La Bodega de Medio (Hemingway's hangout) for some fabulous food. We even enjoyed the cultural exchange that is required on the tour. We also got to go to the Handmade Market (all things Cuban) for some shopping time. We would absolutely do it again. We hope to go back in the future and pick one of the tours not with the cruise line and make our own schedule of where we would like to go.