We're staying on the Dutch side - Towers at MB - and while I really can't speak for elsewhere on the island, we have had virtually no issues with mosquitos to date.
That said, the breezes have changed (as in died?) and last night, DH was a little bit bitten out on the balcony and we're fairly high up but with a lot of beautiful vegetation at ground floor level. Have and use that deet based repellent of your choice. It can't hurt and who knows what it might prevent? Me? I'd rather be safe than sorry later. I keep the Off wipes with me whenever we're outside here. <img src="http://www.traveltalkonline.com/forums/images/graemlins/handshake.gif" alt="" /> <img src="http://www.traveltalkonline.com/forums/images/graemlins/handshake.gif" alt="" />