We tried to use this system for about a year and it was an absolute nightmare. Dropped calls, phones crashing in the middle of a conference call, FXO sound quality was a complete joke, faxing never worked despite using supposedly supported interop scenarios and T.38 set up correctly, and numerous features that were supposedly included with our system were showing as blocked by the license.
When we complained to PBXnSIP (now Snom) and tried to get tech support, they complained to us that we were a direct customer and that was not how they did business, we should instead contact the reseller for tech support. The reseller told us that their only channel of support with PBXnSIP was via the online support forums. It seems that PBXnSIP really went out of their way to try to avoid providing tech support.
PBXnSIP was a total waste of time and money and caused a great deal of frustration. We switched to Cisco Unified Communications Manager Express a while ago and couldn't be happier, unlike PBXnSIP it works reliably as advertised, interop with other products is fantastic. Unlike the Snom phones, the sound quality is actually good too.
