I lived on Cabrita Point in St Thomas in the 80's and worked in the Yacht Charter/Detail field. I also travel the VI or BVI every so often. Was on Anegada for two weeks last November, and briefly in St Thomas.
St Thomas negatives: St Thomas is a crime ridden, filthy, filled with cars way past capacity, taxi drivers who are modern day pirates, trash covered, don't want to go out at night so you won't get stabbed, third world island. Your on your own there if something happens. The hospital was notorious for b people bleeding to death. Every person I knew who was living on the island (not native) carried an air ambulance insurance policy. As it is a territory do not expect any consular help. The police are lazy and have a largely impossible job. As you walk Charlotte Amalie in the p.m. (if your brave enough to walk the back street) you will be offered drugs. Charlotte Amalie is a cheap, jewelry store filled, downtown geared to prey upon Cruise Ship customers. Almost all locals leave doors of cars unlocked as if it is locked your likely to have a window broken.
St John used to be the gem of the VI. Now it is over developed. St John has had a ton of bad press regarding the reverse racism. I talked to a cruising friend who lives off and on in St Croix and the skinny is the rastas from St Croix moved to St John to basically stir up trouble. And Trunk Bay is now polluted with cruise ship tourists and has lost it's charm. Do not go to a bar or club at night as you have a good chance of being stabbed or robbed.
Now for the positive. The beaches are awesome and the water truly inviting. The natives who are nice are really incredible people with warm hearts. If you stick to the daytime spots 99% chance you will be fine. You can bring 6 liters back duty free
. The lush jungle like setting is pretty neat, and looking out watching the float planes land and take off from Charolette Amalie harbor is a sight to see. The diving is incredible, basically nothing better. The cruising is very good, with lots of little bars/restraunts catered to cruiser (Foxy's as an example).
The BVI is really where it's at. I can't say good enough things about Anegada. ZERO crime. Wide open beaches and a chance to walk for miles down the beach with no one but flamingos to keep you company.
Whatever you do if you take some basic precautions you'll be fine. Hope I did not slam St Thomas too badly, but it's my impression of the place.