Hello,
I have read so many posts saying that St. Maarten has poor diving and I would beg to differ. Like any other destination it all depends on the operator you choose. If you decide to go with the big cattle diving ops well then your experience will be mediocre, and this applies to any dive destination. St. Maarten has not marketed its dive industry as it should, and is in some areas lacking proper marine conservation, but that does not mean that there is no good diving to be had on the island. It is true that the dive sites on Saba and Statia are of higher quality, but if your experience level does not allow you to dive the relatively deep sites in saba, and if you are looking for a more developed tourism infrastructure than statia, well then st. maarten can be quite rewarding.
On St. Maarten I would definately recommend Ocean Explorers on Kim Sha beach. It is a relatively small op run by a husband and wife team who offer exceptional service. It is the only op that offers the shark awareness dives (the other ops tag along when those dives are being conducted) and will cater to your experience level and what you would like to see. They can also dive lesser known sights depending on your experience and the conditions. On your surface intervals you can enjoy the many topside activities the island has to offer. If anyone needs more info feel free to PM me.
Good diving,
Tadzio