I talked to the officer that patrols our neighborhood about his. He likes it.
He said that it has been used several times to invalidate complaints. He also mentioned something interesting: the people that rant and rave during a traffic stop are never a problem -- apparently they just want to vent.
The complaints come from people that are cordial and polite, then conjure up a fictional conflict afterwards.
Any cop ranting about having to wear a body camera is unhinged in my opinion and should immediately have his gun and badge taken from him and be sent to the shrink.