I have a 3 site, 100+ extension Shoretel deployment here in the central USA.
We have had it for nearly 2 years and have been plagued with issues since day one. We have had every sort of network tech, phone tech, provider tech and Shoretel themselves on site on several occasions and no one has been able to repair this thing.
Issues include, problems with communications over WAN links (MPLS PIP) volume pitching up and down, unreliable Softphone performance, DTMF tones not being registered on some systems and unreliable faxing.
We are on the verge of scrapping the whole system and moving to another solution such as Avaya or Cisco.
I will add however that if you are a very small (20 or so phones) on a single site then the Shoretel system makes it pretty easy to administer. However, if you need 50+ extensions at multiple sites, I suggest moving away from Shoretel.
