Hope this helps
I live in Sint Maarten and have dived both here and in Saba on many occasions. If I were to make a subjective observation I would say that Saba offers a more varied diving experience than SXM. It has walls, pinnacles, volcanic and organic formed reefs, which offer very diverse diving conditions, this is of course assuming the weather conditions allow you to visit the many sites on offer. In my own personal experience due to wind, current and sea conditions I have never been able to visit all the types of sites on one visit, let alone one day.
As for getting to Saba, this depends on how long you are going for. If just for the day then the plane offers the possibility of fitting in three dives, where as with the ferry you can only make two. The plane takes about fifteen minutes (flight time), and if you get the first flight out you will have time for breakfast in Saba before you start diving, the last flight leaving gets you back late afternoon, early evening. When flying you will need transfers to and from the airport to the harbour, this can be arranged by the dive shop in Saba (I always use and can recommend Sea Saba). The ferry leaves at 9:00 am (booking in at 8:15) and takes about 1.5 hours, which gets you into Saba in time for the second and third boat dives, before returning on the ferry at 15:30 pm. Transfers to and from the ferry are just a matter of checking in at passport control and walking along the jetty between the boats. So the advantages of flying are you can fit in an extra dive, and if you suffer from sea sickness it's much more comfortable (and quite exciting when landing and taking off in Saba), especially as you will be getting onto another boat as soon as you arrive. The disadvantages are it costs more (about $180 vs $100 per person), you may be limited on how much luggage you can take, which may be a problem if you have a full set of dive gear plus camera's etc. This has never happened to me and only occurs if the plane is full, when weight restrictions may apply, should it occur then you stuff will be put on the next available flight, but if you are only going for the day this might not be ideal. Assuming you don't get easily seasick the ferry offers a good alternative to flying, especially if you intend to spend a night or two on Saba, unlimited luggage ($5 for every extra suitcase) and you only miss one dive on the day of arrival.
OK, that's Saba pretty much covered, now Sint Maarten! When I first visited and dived here back in 2008 I wasn't very impressed, I tried a couple of dives but they were not the best and with the exception of the shark feeding dives, which were fun (they've stopped them now), I was disappointed, hence I used to always go to Saba. However since I moved permanently here I decided to investigate more options and different dive operators, and manged to hit on "Ocean Explorers" based in Simpson Bay. Having now done more that 50 dives with them my opinion has changed completely. Although SXM does not have the dive site diversity of Saba, it does have it's own character which is broadly split into two main areas. Directly out front of Simpson Bay and to the right (the more Caribbean side of the island) is a more sheltered sandy and sea-grass area which has some wreck dives, which although in my opinion not beautiful to look at, do attract sting rays, turtles, and schools of fish, which you can see on almost every dive. My preference is to the left of Simpson Bay around towards Great Bay (the more Atlantic side of the island), where although the sea can be a little rougher you will see some beautiful reefs such as "Fish Bowl", Maze", "Cable" and the wrecks "Proyselyte" and "Carib Cargo". On these sites you will nearly always see Nurse Sharks, Caribbean Reef Sharks, Turtles, Rays and of course a variety of beautiful Caribbean creatures. I should also say that the sharks are very friendly and come very close to the divers, probably because of the previous feeding policy, this does however make for some great photo opportunities.
I still haven't explored all that SXM has to offer as I've yet to do the dives sites "Moon Hole" and "One Step" which are further around on the Atlantic side and require that the sea conditions are excellent before they can be dived. I also have the French side of the island to look forward to, I've heard that the diving between SXM and Anguilla is also good, so that's also on my "to do list".
So in summary both Saba and SXM offer great diving, the major difference is that there is some "poor" diving in SXM. If I were planning a serious dive trip of a week or two and nothing else (there really is nothing else to do in Saba unless you like hiking), I would probably choose Saba, and keep my fingers crossed that the weather would allow me to visit most of their spectacular dive sites. However if I was looking for a more rounded holiday, beaches, bars, restaurants, supermarkets, shopping etc. and of course also wanted some great diving I would choose SXM. I think ideally I would do a little of both, the main stay in SXM with a couple of nights in Saba.
My biggest tip when visiting SXM and Saba (this probably applies to all dive destinations) is find a good operator, my experience here confirms this and I can definitely recommend "Ocean Explorers" with Jeff and his team in Simpson Bay, and "Sea Saba" in Windwardside.
I've attached a few pictures I've taken in Sint Maarten over the last month to give you and idea of the type of diving.
Hope this all helps if you need any more info let me know, gotta go now it's Saturday morning and the wife is calling it's time to go shopping
