Jamaica had cool excursions, but the vendors were aggressive. I just started walking fast and ignoring them when I was done buying. Dunn's River Falls was more than we bargained for, but I was glad I did it after. The Bobsled ride was cool too. Such beautiful scenery.
Grand Cayman has great snorkeling. Stores were more as Americans are used to. Didn't see anything other than the stores and the snorkeling excursion. Though my friend went to 7 mile beach years ago and LOVED it. She would go back to Grand Cayman for a week by itself.