I've written several times about specific restaurants that HB and I have visited, but nothing about the restaurant culture on island in general. What kind of experience can someone expect when they go out to dinner (or lunch, or breakfast) on Tortola?
There are essentially three types of dining establishments on the island: those that cater to visitors and expats; those that cater to West Indians; and bars. Government prohibits franchises, so all restaurants are pretty much one-offs, except Pusser's, which is a locally owned chain.
Service pretty much everywhere is slow and rarely customer-oriented, which can be a big difference for someone from the US or Canada, but is not unlike service I've encountered in Europe. The exception to this rule on Tortola at least is the Sugar Mill.
Bars provide pretty much the sort of bar food you would expect, with burgers, sandwiches, pizza, and the occasional roti or pate thrown in. West Indian restaurants, unsurprisingly, offer a variety of West Indian cuisine, like ox tail stew, curried goat, ginger wine chicken, and shrimp creole. Entrees at bars and West Indian restaurants generally start around $10 and go up from there, with large pizzas typically costing around $20.
In sharp contrast are the restaurants that cater to visitors and expats, which provide a pretty standard rotation of continental fare, with the occasional French or Asian fusion flair. Sky Bar is perhaps an exception to this, as they specialize in teppanyaki and sushi. A visit to one of these restaurants is usually accompanied by a fair bit of sticker shock on my part, as vegetarian and chicken dishes usually start around $20. While often the quality of food is not much different from what you'd find at an Applebee's for half the price, there are a few of these restaurants that offer a better overall value through higher food quality or better service.