I have magic jack but after I initially installed it I never used it. The service is terrible and I wouldn't be surprised if they had vacuum tube mainframes and tape drives running thier repeaters. Having said that, magic jack is extremely valuable for one thing: a number I can quickly forward to any phone I please. That's why I keep the phone number. Once I need a number for people to call I can have the magic jack number listed, and simply forward it to whatever number I'm using at the time(though it won't forward internationally).
Not really. I have the number for 5 years and I don't have to pay a dime for it again until the renewal. Plus once it forwards the call it goes off their switchboard so I don't have a problem with the miserable call quality magic jack is famous for. Who knows if I'll renew(or if the company will even be in business) when the time comes but until then I've got a number anyone can call effectively for free.