Most people who are aware of VOIP think that it's cheap primarily
because of some great digital technological breakthrough. They don't
realize that virtually all voice traffic has been digital for a very
long time. In the case of existing phone lines, the A/D was done at
the switch at the local phone company. From there on through the
network it was all handled digitally, running through exactly the same
kind of fiber optic lines and other high speed digital lines as the
internet, until it was converted back to analog at the far end. The
big difference was that the phone system guarantees that every digital
sample arrives at the other end at precise intervals that correspond to
the 8khz sampling rate. With VOIP, the packets can be routed all over
the place, with no guarantee that they will get there at the right
time. That's a big difference in quality of service.

Most people who went to VOIP did not do it to avoid the $20 monthly
local phone service fee. The did it because they had high toll call
bills, with a lot of that likely being over seas calls. So what they
were avoiding was the regulated tariff structure, both domestic and
international, at the the expense of reliability. Along the way, many
found out that there are in fact some serious problems, like the 911
issue and call quality. And also, since we're on the subject of call
monitoring, do the major monitoring services work with VOIP? I know as
of a couple years ago, they had a policy of not supporting it. The
domestic long distance cost has dropped sharply over the last few
years, with most providers now offering some form of bulk or unlimited
calling packages at more reasonable rates, so the incentive to switch
keeps dropping.

And today statements like:

"Those of us who actually use VoIP every day might tend to
disagree with you. I've had the service for over a year. At
first there were major quality and reliability issues so I only
used it as an overflow for my POTS lines. "

hardly bring a ringing endorsement. If there were major quality and
reliability issues that recently, I'll just stick with Verizon.