[guylhem]

Is there any similar service where an existing GV number could be ported?

I was with sipphone client before it turned into gizmo5 and was swallowed. I remember the pains of reconfiguration (hardware ata + sip enabled dect phone + handheld + desktop + laptop ...), and pushing the new phone number to contacts, including the fact that to this day my sip-enabled dect phone at home still can't make outgoing call using GV.

I don't want the same scenario to repeat itself - I'll pay for the privilege of not having to wonder whether the service might close or not.

[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.