Here's my experience for what it's worth. For the first 5 years I owned my boat, I used Trinidad SR. I found I still had growth well before the season ended and had to re-paint the next spring anyway. On the advice of an old salt in my club, I switched to the cheapest paint I can find (usually West Marine's BottomKote) and have a diver wash the hull once a month. I still have to paint every season, the bottom is cleaner thanks to the diver and my costs in total are about the same, maybe a little less.
I sail out of City Island, so conditions should be the same as yours.