Maestro is simply the debit version of MasterCard.
True but doesn't make this any less accurate ...
Maestro cards do not work at most point-of-sale terminals in the United States. You're going to be limited to ATM access.
While Maestro is a debt card version of Mastercard it is virtually unheard of in the US and as a result almost all POS machines will simply reject it as an unsupported card.