Well I have to worry about this because I download Files which contain Viruses.. the reason for scanning is just this scan everything, What's the purpose of virus scanners if they do not detect and get rid of viruses?
Free or Paid for, to me...all the people who write viruses to harm people or cause havit should be lined up and shot.
If you could sit down a write a virus you have to much time on your hands.
The shooting comment is just a figure of speech, but all the virus writers should be tracked down and dealt with.
way back before the net I ran a bbs and had a user try to break into my system and delete my HD and all my users wanted to beat the living crap out of this person. and that was a long time ago.