If you have a G.722 capable voip desk phone or softphone on your own asterisk system, where G.722 calls work between any two extensions on your system, and you

If you have a G.722 capable voip desk phone or softphone on your own asterisk system, where G.722 calls work between any two extensions on your system, and you are making calls into the regular PSTN... It is almost certainly ending up as G.711 anyways if you're calling another carrier. Particularly if you are using a SIP trunking service to reach any international destinations outside of the US50 states and Canada, it's going to be regular G.711 alaw or ulaw.