I spend several weeks each year in Africa and used to pick up a SIM card at the Johannesburg airport. I now have an international plan for my phone that is fairly reasonable, especially for texting. I am assuming this is the gist of your question?
Can you provide a few more details of what you are trying to accomplish?
I see that you got advice on the Boston forum to post here asking about reliable providers. I can tell you to cross T-mobile off your list if you will be in the midcoast. AT&T can be spotty, but is better than t-mobile. Verizon is more reliable than either. In some parts of Maine, people swear by US Cellular, but their online assistance is horrendous, so for a short visit I would probably go with Verizon.
CB48 - thanks for the very good advice.
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