Aliwei Communications vs NexVortex

We switched over from Etherspeak in May of 2012. We are a Cisco re-seller that deals with everything but VOIP. I checked into fully managed VOIP and SIP setup with Charter, AT&T, etc. They all wanted big bucks for not alot of function. We did not always have the best experience with our previous SIP provider, and decided to give SIP one last try before going back to old PBX/POTS. We have had a very good experience with NexVortex so far. I can only speak regarding the features we use. Our shop is all Cisco Unified IP phones, with a Cisco UC540 phone system. I have NV setup as a SIP trunk directly into our Cisco UC540, over a dedicated SIP/voice T1. Since we are are a small company, we only use around 12 lines at a given time. We also have 2-3 remote users at a given time tunneled back to the main office, all using the same SIP phone system. I can tell you it all works perfectly without issue. Our biggest concern in switching to NexVortex was uptime/reliability. We did not have the best experience in the past with other SIP providers. I can tell you that is completely different with NexVortex. They are not perfect, and did go down one time in July. Fortunately that outage was only for 30 minutes, and we have not had a single other issue. This is far greater reliability than we have experienced with any other SIP provider. I love the online interface, and specifically the disaster recovery feature. It has saved us a couple times when our T1 went down, as it automatically sent calls to the old POTS lines. Their billing is accurate, and the rates are reasonable. The call quality is good, even using g729 codec which is what we use. It's one of the few VOIP companies we have found that actually delivers what they promise, at the rate they promised.