I found this comment on another board about Belize. I have had no personal experience with this place and do not know about the poster's reliability.

We stayed at Roberts Grve in Placencia which was very nice. We decided to go to Soulshine resort and spa "on it's own privates island" for a massage and dinner at their spa. Well, the private island is a piece of land on the lagoon! with no beach. The "spa" is a cement room with a thatch roof, a massage table and two bathtubs (not hydrotherapy). The surroundings were totally disappointing, we decided not to stay for dinner to say the least. BIG FALSE ADVERTISING!!!

No matter where you go ... There you are!