This is a brilliant phone, and the service from voipon was great. Delivery was on time and checkout process was easy.
I'm new to VOIP, so had some issues setting it up, but it turned out that I had a settings called "SIP AGL" turned on in my router that my phone was sat behind and this was causing issues (the call wouldn't pick up when it was ringing). I turned SIP AGLoff and everything started working. Just thought I would mention it in case anyone else runs in to it.