Single anecdotal counterpoint: My corporate VOIP system is made of Polycom phones connecting via SIP to local Asterisk servers, and then those have interconnec

Single anecdotal counterpoint: My corporate VOIP system is made of Polycom phones connecting via SIP to local Asterisk servers, and then those have interconnects to PSTN gateway services. The quality on-campus is uniformly extremely high. Some people have the Polycom phones at home (for working remotely) and calls to/from those are of similarly high quality, even in conferences. Connections to cellphones range from mediocre to bad. Connections to POTS land lines range from bad to pretty good. Overall I would say that our VOIP system doesn't have a problem.