It's better than spysweeper, which takes alot of system resources, (increases Windows login time by 2 minutes!!! with 2GB RAM, Pentium 4, WTF!!!) and annoys you constantly about doing a scan even if you just did one, or about updating it when it just has been, or alerting you that it didn't shut down properly for no reason, or even occassionally screwing with windows so that shutting down makes the PC freeze on the desktop with no icons, no buttons, no controls. You have to pull the plug. Oh and it costs $35 a year....
I like McAfee (which came with my ISP for free) and Avira alot better.
Oh and it would be "viruses".