This year marks at least our 48th consecutive year of annual trips to SXM, Going at least once a year and many years more often than that. We have NEVER felt the need to exchange US currency for local. And in fact, I don’t think I ever saw either a franc or a euro and for sure, no Dutch currency.
As suggested we use fee free ccs wherever accepted and US $$ everywhere else. Never had a problem and one less thing to deal with in the overall scheme of travel.