Vonnage hands-down. 
No need to have computer running like magic jack.
Can do all kinds of neat stuff i
ncluded-word wide long distance no charge, forward to any number,caller ID and all the extras like that are included-3 way calling etc.
Track all calls in CP. Can get toll-free for $5 a month extra. No complaints at all and price is VERY reasonable ($24.99 for 1line)
Just great service and in at least 7-8 years have
Never had anybody ask if I was on something besides "land line" even when calling Italy & such. So quality is superb as long as you have high speed provider.
Takes about 128k of your connection. On my 6KDSL have had kids playing games, me logged into servers doing work for customer while they were on phone, wife using her computer and then a fax comes in---no problems or slow downs for anybody and I don't have new high speed wireless yet. So I have no complaints in all these years.
Maybe a modem re-boot 1-2 times a year because DSL dropped off and had to get all the connections"taking" to each other again but that's' only 2-3 minutes down twice a year or so - no complaints with that-it can happen to any router.