Manual hits or autohits?

Theoretically, if you look for people to know your site and/or products, your preference should be for manual traffic. If your goal is to achieve better rankings, you should turn to autohits.

In reality, a good advertising campaign includes everything: manual traffic, autohits, text and banner exposure, etc.

HINT:
if you want to promote an affiliate page, you don't need autohits. In fact in most cases, if you DO NOT own the domain, you are just wasting your money.
On the other end, if you DO own the domain, you should try to receive autohits on all the pages of your site.