To me, I think your best shot would be somewhere in Simpson Bay, to be close to the action The best place to me, if you are determined not to rent a car, would be Royal Palm.
I think you are a regular BVI person, which could mean that you comparing SXM to the BVI. Cars in SXM are DIRT cheap, as compared to the BVI, and in SXM, you do drive on the 'correct' side of the road, versus the BVI. So you might want to reconsider the no car deal. Most folks who go to SXM travel around to different beaches while they are there and many or most don't just hang out at the beach at their hotel.
Regardless please do post any other questions you have and enjoy your trip!
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