I haven't tried it. It's a moot point anyhow, since saving the configuration on the OBiTALK portal is broken, so I can't test it. I can, however tell you that it wouldn't save the GV authentication credentials (OAUTH token), nor would it save any other service provider SIP passwords. This is by design, for security purposes. See pages 44 and 45 of the OBi admin guide for details.
Saving and restoring the way Robert described is the best alternative. You simply need to re-run the GV account setup, and, if you use any other service providers, re-enter their passwords.