I can roam and check MIN BAL on my phone. I typically connect to T-Mobile or AT&T network. I top up online to to keep my SIM active throughout the year and sometime send any extra credits to someone I know in JA. Currently I can check my MIN BAL and receive messages but not make calls or send messages. Maybe I need to top up again but I show a MIN BAL. This happened once before and digicell was able to correct via a chat session.
But if you are connected to a GSM network (e.g. T-Mobile), you should be able to roam in the US and use most features (voicemail needs to be dial directly).
