When in the Bahamas last year, we put our Verizon Air Card and our two Verizon Cell Phones on vacation hold.  The money saved over that 2.5 months almost paid for the Iridium phone we rented from Explorer Satellite.
We also used MagicJack for calls to the US.  It worked very well when we had a strong WiFi signal.  Our friends used Skype which worked as well but costs more than MagicJack when connecting to a phone, not a computer.  Skype also required headphones; MagicJack used a cheap landline phone we purchased.
We have no financial interest in Verizon, Iridium, Explorer Satellite, MagicJack or Skype.
Barry