We recently returned from 10 days on Saba (a 13 min flight from St. Maartin). We loved it. A perfect 5 square miles of relaxation. The dive conditions weren't 100% optimal, but even though it was my first time with my wide angle lens, the pictures weren't bad! We dove with Sea Saba - they also take care of everything - I mean everything - dinner reservations, grocery shopping, anything. We found the dive masters to be knowledgeable, relaxed, and absolutely no pressure to end any dives before you wanted/needed to. Because the island is preserved as a marine park, the fish have alot less fear of people than in other places.
For lodging we rented the Iris House and loved it. Enough restaurants to keep us entertained, outdoor movies, some interesting hikes (everything is straight up or straight down), and the friendliest taxi drivers you will ever meet. During the summer, there were about 25 tourists on the island in total. That's our kind of place! Add the most exciting landing and take-off you might ever have and it is definitely a place we fell in love with.
I'm happy to answer any questions anyone might have about this locale