Monday night grand buffet is also very good with a tremendous variety of food of all types. The Turtle bay restaurant is somewhat more expensive than the others if you are paying ala carte - be forewarned. Other choices are the SugarMill and the Caneel Bay Restaurant. All three restaurants have nice views. If paying ala carte, you simple pay for what you order.
Alcoholic drinks are extra but soft drinks are free, by and large.
If you plan to stay at the resort and not sightsee, the full plan is probably the better deal. Otherwise, go ala carte. We went to Tortola for a day - very hot which made it uncomfortable. But if you go, be sure to go in the Sunny Caribee shop in RoadTown. A cute shop with exotic teas, spices and so forth.