Given my past comments on this thread, I feel I should report that since the last software upgrade a few weeks ago everything appears to be normal. The issues (dropping calls, static, unable to register, and on and on) have all been resolved as far as I can tell. The speakerphone sounds terrific and I have come to use it very heavily since gaining confidence in it.
I will maintain that the process that got us here was absolutely unacceptable, but I won't dwell any further on it. As far as I'm concerned we have a stable phone system and anyone who is still interested should feel comfortable with making the purchase.