Howdy, Tim -
John and Ted hit all the highlights above, so I'll just piggyback on what they said a little bit.
Our weeklong charter was five years ago with Barefoot on St. Vincent. We had a great experience with this smaller, independent charter company!
Our itinerary was similar to John's, but we pressed on to Mustique the first day. Mustique is a bit shee-shee-poo-poo fancy, but Basil's floating bar is actually laid back and lots of fun. Their annual Blues Festival is going on there for the next few days. Probably a bit busy through 10 Feb.
This was my first experience with the Tradewinds, and they were something else. 24/7 we never saw less than 15 knots. 20-25 seemed to be normal for our March week and we had 30-35 on the last day.
The first passage between St. Vincent and Bequia seems to be typically the roughest, from our experience and from what I've read. We had 8-ft swells and 25 knots of wind right out of the harbor on the way down.
Winds were pretty much on the beam all the way down the island chain and back up. Most days we had 15-20 knots and 5-6-ft swells. This sure made for great passages.
Tobago Cays is the crown jewel of the Grenadines. Anchoring inside of the huge horseshoe reef is a unique experience. All the surrounding islands are uninhabited, which meant no ambient light at night. We had the most amazing horizon to horizon canopy of stars in that anchorage at night. Great snorkeling, too.
The highlight of our trip was hiring some boatboys to set up a lobster bbq on the beach for us one night in the Tobago Cays on a deserted island. They picked us up after dark in their home-built boat and zig-zagged through the reef without lights....eye-opening to say the least, but they sure knew the waters!
They had a bonfire with a grill on it, roasting some gi-normous, Jules Verne, Creature of the Deep lobsters for us. Bring a good bottle of wine!
Our last passage back, from Bequia to St. Vincent was where we saw the 35 knot wind and 15-ft swell. Sporty, but we had a blast on our 44-ft Gib-Sea.
You will have a great time! I haven't sailed much in the BVI, but from what I gather, it is the Bunny Slope of sailing charters and also crowded, with skippers fighting over moorings, etc. The Grenadines are more like Blue Square to Black Diamond sail chartering, less crowded and much less developed....Mustique aside.
Have fun, and give us a full trip report!!
Curt