[agwa]

If you're just looking for a decent SIP service which lets you place/receive calls on the PSTN, take a look at these companies:

http://www.callcentric.com/

https://www.anveo.com/

https://www.voip.ms/

All three are well-established companies, though Callcentric is probably the best. I've personally ported a GV number to them. The service isn't free and you don't get voicemail transcription or a fancy web interface, but it's reliable and very good at making/receiving phone calls.