Should I get a Magic Jack?

We have been going back and forth on this Magic Jack issue for 6 months now. There are so many complaints about it, but we cannot afford a month to month or contract phone service and we did the free trial of MJ and found it to work pretty well (1 complaint out of talking to about 30 people). Walmart's manager said that he will refund my money if I am not satisfied. Is this worth my $38.88 to buy this device + a cordless phone, or should I forget it once and for all?