It's been awhile since I sailed out of Charlotte Amalie, but here is how I would sum it up. Pros: no ferry hassle, north side of St John is very nice. Cons: must (no option) immediately sail into the prevailing winds (was called "Seasick Alley" when I did it), very limited dining options ashore on St John. The time factor depends on whether St John appeals to you more than the anchorages in the BVI that might be on your "to do" list.