I use vonage so my wife can call home to Brazil, and i used it so i could call her when she went back for a year. heard a lot pf good about skype, and ive never heard about magicjack.
Im really impressed with Vonage. for about 30-40 dollars a month, we could call Brazil (or any of about 20-30 other countries), be on the phone nonstop for a month, and the bill would still be 30-40/month.
i used to use a service called broadvoice, and they were trash. besides a bad connection, they shut me off of unlimited service to Brazil for a month because "i used the phone too much" and had no criteria that specified how much "too much" was. needless to say i was livid and after reporting them to the BBB and threatening court action, i told them to kiss my brown wrinkly spot and canceled (and they tried to stick me with a cnx fee, but i cut that crap real fast.) i explained to Vonage the problems i had been going through and told them i was shopping around, and they gave me a good hookup to pull me in. and i have had no problems with Vonage at all. Crystal clear (unless youre downloading a really large file) and easy to hook up, even with a VPN wireless router.