You Decide
Decide to either upload a message or have the auto dialer call you to record your message over the phone, then add as many messages as you want and determine what campaign to use them for later.
Seperate Messages Played
You can have the auto dialer leave one kind of message for live answered calls, and a different message to play to answering machines. That way, you can have the live answered calls press a key on their phone to speak to you now, and you can leave a number for answering machines.