Grand Turk, we did the Gibbs Cay Stingray Encounter. The tour company was great! They were able to find a (one) small male stingray for everyone to take pictures with. We had our own waterproof camera and they encouraged us to take our own pictures instead of buying them at the dock through the company. They also provided snorkeling gear and training to those new to snorkeling. It was a good excursion, I recommend it.
Montego Bay, Jamaica, we did the Jungle River Raft/Float Tour. It was a long ssllooww tour down the Jungle River tied together with others while our tour guide paddled his arms off. I don't think I can recommend this excursion, it just seemed long, boring and awkward with the tour guide paddling our butts down the river.