What kind of a vacation are they looking for? If they aren't big drinkers, there's not much point to an AI on SXM. (IMHO) The Sonesta does have a nice pool, direct access to Maho beach and an easy walk to Mullet. So if they only have a few days, that might be a big plus for them. However with so many good restaurants in Maho now - let alone the rest of the island - it would seem a shame to limit your dining options to whatever the hotel is serving up for you. If they are looking for cruises and water sports, they might find something in Simpson Bay more convenient. If they are big drinkers on a limited budget without much time, the Sonesta might work well for them - outside of that, I think there are better options.