see this for a comparison of detection, removal and impact on system from av-comparitives
(yes its a trusted site with millions of viruses unlike top.ten.reviews..... huh random ads and when i watched one of their videos you can tell the guy has no idea what his saying lol)
note: this only tests anti virus and internet security. HIPS dont need testing lol....
EDIT (By knicksfan3): You're not allowed to link to the Av-comparatives PDF File, you can only link to the main site.
All 4 computers:
Avira Free (scanner only installed)
EXPECT THE WORSE, PREPARE FOR THE WORST