Shifty gave a great reply, but I'll just comment about a couple of things. We have chartered twice from Moorings (pre hurricane) and once from CYOA (earlier this month).

CYOA was good. No complaints there. We had some technical questions during the charter and got very quick and helpful text responses from CYOA.

St John is our new favorite place with Maho Bay a wonderful place for snorkeling (turtles, rays and SY A was nearby).

Provisioning: Moorings has the edge. We did "split provisioning" first time which was easy but resulted in an oversupply of some things (e.g. fruit juice, nuts). Second time we just used their a la Carte provisioning which went well. At CYOA we tried to provision ourselves and they directed us to Moe's on the harbor front. This turned out to be a small, expensive store (having said that our comparison for prices is the USA so we might be shocked anywhere in the VI). We would try the big Pueblo near Kmart next time.

C&I Jost: Doing customs and immigration at Jost took some time (the boat didn't have enough or the right forms and filling six immigration forms is time consuming) but only the skipper needs to go. The C&I people there are pleasant and helpful (two out of three anyway). Definitely better than ferry/Tortola. It is not cheap.

C&I St John: We tried CBP ROAM but after 1.5 hours waiting we decided to go in person since we were worried about dealing with this on arriving in Charlotte Amalie next day (someone at the airport told us they waited a day). The dinghy ride from Lind Point is long and wet. The C&I people in Cruz Bay did not try to provide a stress free welcome. The forms were available on our boat which helped with an otherwise less than fun experience. Still mooring at Lind Point puts you next to a lovely beach with snorkeling. So the day ended positively.

The start and end: You need to travel from Charlotte Amalie to at least Christmas Cove on the first day (and back on the last). This took us about 1.5 hours I recall. It was a bit rough (like say going to Anegada - look at the NOAA prediction) which was OK for us but might worry first time sailors. You have to fill with fuel at the end of the trip. The fuel dock staff at Yacht Haven Grande are very helpful and pleasant.

One odd thing: Our briefer told us we were forbidden by CYOA to gibe the cat. Maybe this was a reflection of our rather incompetent display of seamanship at checkout (not having sailed together for 2 years is the excuse, but lets leave it there). Still it makes sailing down the Francis Drake Passage a little unusual.

Overall our sentiment is we would use CYOA again.