Couple of times I tried using it, the reps were super confused and kept asking me to reveal the name of third party on the line. As a joke I once replied Google Androidov and the guy just wrote it down.

Some straight up refused to speak to me because of third party on the line.

Most just hang up as soon they hear any kind of automated message.

I wish there was a silent mode at least available to single party consent states or for a list of numbers that tell you your call will be recorded without an option to opt out.