We initially chartered in the BVI many years ago and now have chartered from SXM for the last three years. We love it. Note that it's just me and my wife on the charter - we don't bring any kids or other people along so it's got that kind of skew for what that's worth. Also, we go in the low-season so the number of charterers is reduced even more.

I agree that SXM doesn't have the charter-centric feel that BVI has but there is a pretty big Moorings/Sunsail base and there are a few other smaller outfits as well. In general, at beach bars and restaurants, you don't tend to run in to fellow charterers. In fact, most people look at you like "Why in the world would you not want to be in a hotel?"

There isn't the Drake Channel type of protection around SXM. In fact, when I was first looking at boats to charter, it was funny to see that the smallest mono they rent at the Moorings is a 43 "due to the amount of open ocean sailing". I wouldn't necessarily call it open ocean sailing but it could get rough.

For overnights, you will mostly be anchoring. There are a few moorings in some of the marine parks such as Tintamarre and Pinel and at St. Barts but on our last charter, the Moorings rep suggested that we not use them because they are not trustworthy. You are supposed to pay for those moorings if you use them by paying a park fee at the charter base although I'm not sure many people do.

As another person posted, the anchorages inside Orient Bay (Pinel and Green Cay) are shallow and getting a keelboat in is dicey. We did it but we are thinking of making the switch to a cat next time (ugh) just to make that part easier and less rolley.

I could go on but I have a few blog posts that go into more detail if you want it.

I'm happy to answer questions if you have them. All in all, we recommend chartering in SXM.