Flying into these airports is likely going to be as interesting as the rest of your trip put together.
I've been to Saba and St. Martin. The Princess Juliana airport strange, but it is safe. You just don't want to drive there if there is a plane near. You might get blown off the island if you are really unlucky.
The above picture gives you a better image of the runway on Saba. The runway is only 400 meters long, making this more like landing on an aircraft carrier. If the pilot can't stop in time he will need to take off again. Also, takeoff is really weird since you pretty much throw yourself off the rock.