Two issues immediately come to mind when considering deployment of body-worn recorders. First is the concern for privacy. Some systems don't alert others when they're recording, and it's easy to forget to turn the recorder off after a call or traffic stop.
So casual conversations with the potential for embarrassment can wind up in your evidence files. You should consider establishing a policy on the use and retention of communications between department members, especially when there hasn't been explicit notice that a recording is being made.