i also have Tmobile. Yes, it may be a bit slower on SXM than at home, but for the most part it works GREAT on the island. Text is free, and if you make a call its only twenty five cents a minute. Most places on island offer wi fi, so between whatsap, and aol messenger, our bill from Tmobile for all our calls to and from the USA was like ten bucks. Even that could've been lower, but answered every call.
IF you plan on spending hours on the phone, while on vacation, then it may be worth the ten bucks or so a day for international, but an occasional quick call, it's a GREAT deal just the way it is. I LOVE Tmobile.
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