We've have been installing iProphet for three years now. These are the same guys that developed the ProphetVoice voice mail system. The same system as the NVM voice mail for NEC. Albeit, a very robust and dependable system.
The iProphet SIP phone system is equally as outstanding. SIP trunks are easy to install and beats the pants off of PRI. Not all SIP providers are good. We learned who was good and who was bad. SIP providers pop up like zits on teenagers...beware.
We were fighting this technology shift as we were a big Nortel, Samsung and NEC house. This was difficult at the beginning to accept especially since the first Generation of SIP solutions seemed to be written by IT guys without a clue of Telecom. I can say without hesitation that we have NO issues with nearly 100 installations ranging from 6 users to 75 users. Oh, and the networking between systems is a breath of fresh air.
My 2 cents...
