Two Retail VoIP Carriers I would recommend

If you need to use your SIP softphone for some manual dialing and get good rates and good quality, try out FreeCall and VoipBuster. What do they offer?

1. Good Clean Standards based VoIP Connectivity using SIP
2. G.711, G.729 and iLBC codecs
3. RFC 2833 DTMF
4. Full NAT Traversal capabilities (no STUN required)
5. Good quality
6. Cheap rates with lots of free calling within U.S