Most of the major security suite vendors release their new editions in the fall, but some run ahead or behind the rest of the pack. With the release of  Kaseprsky Internet Security 2009 the fall flood of security suites has officially begun. I'm working on two other suites right now, and by the time I finish with them the flood will be in full spate. This year I'm adding a new kind of testing to see just how much performance you're giving up in exchange for security.

I hear tons of complaints about how this-or-that suite slowed the computer to a crawl, added minutes to boot time, or made web surfing unbearably slow. But I can't rely on anecdotal evidence for reviews - I had to develop some repeatable and quantifiable tests to see just how much a given suite affects performance.

Source: http://www.appscout.com/2008/08/security_suite_performance_tes_1.php