What SIP provider do you use? Which provides the BEST performance and call quality. (Including codec support and call quality overall) I am doing a demo on SIPTRUNK.COM which seems good, but there are a few minor quality issues. They only support G.711 and G729. We have Fiber so not too concerned about bandwidth usage (Last speedtest reported 300/down), just looking for suggestions on handsdown best quality SIP provider. Do you stick with larger names like AT&T or go to the smaller companies out there? We have a private DataCenter and are moving into reselling PBX systems. We want to go with a company who can provide best quality calls for our clients.