Best in what way?
What are your test parameters?
BTW, no need to type your name in the subject title. We can see your username.
The best defense is the user. Let's say you run Windows. Most of the damage today is not a virus so that's not how they infect your PC today. Today they bundle in unwanted apps and toolbars which might install even if you opt out.
Then we have torrent users that get hit with the most odd infections.
You are the best protection.