That depends upon the system. Some "VOIP ready" systems are more ready than others. The main difference as I see it is that systems like the Allworx are targeting the medium-sized businesses, which can use their own WAN network. Many of the VOIP-ready systems need to plug into a WAN, and their only VOIP-readiness is that they can use VOIP phones as well as digital phones.

The only advantage I see for systems like the Allworx is free toll.LD calls between offices. I would like to know any other advantages over digital phone systems as well!