I've just been away for a couple of weeks on holiday, with no internet access (from choice). It's been bliss. I haven't set an autoresponder message on my email, nor did I put an "I'm away" message on my voicemail. That's partly because I have other people to check them for me, and send a holding response if necessary. However, even when I was a sole trader, I never set up auto-replies.
There are several reasons why I didn't:
1) The remote possibility of alerting people that my home and office are unattended.
2) The fact that it alerted potential clients that I was a one-person company. That could be off-putting for large corporate clients.
3) I can't see the value of it anyway. If people need a quick response, it doesn't help, and if they can wait a week or two, you can respond on your return.
I've never been aware of any business that I've lost as a result of responding on return from holiday. Normally, our response (usually from my business manager) is very fast. However, it seems to me that clients are perfectly prepared to wait.
Finally, some people are either on holiday for months (lucky them), or forget to turn their autoresponder off. All in all, I can't see the value of "Out of the office".