I used magic jack for a year. Actually didn't have problems. I heared everyone well. Some people felt I sounded like I was in a big hall. I used my web cam as the microphone and my laptop speakers .., It did come in handy when in a hotel but I guess you can use your cell.
What I use for free long distance is google voice.
www..google.com/voice.
All you need is a phone. I have it linked to my home phone, office and cell phones. Which means if someone calls you on your number it rings on all phones you link to it. So I can get a call, answer it from my office and drive my wife crazy cause she heard the phone ring at home but since I beat her to it, no one is there!
You can go on line and use your contact list to make a call and even send free text messages to cell phones. If you're not online, just call your number from one of your linked phones, enter your password and you can make a call or receive voice mail.