AVG turned into a real pig - too bad, since it absorbed Ewido Anti-malware, which was a great program (that's why the anti-malware side of AVG is so good). Avast, Avira and MSE are all more effective AVs. though, and much lighter on system resources. I use Avira myself, it's consistently at or near the top in tests.
I also run Malwarebytes' and SuperAntispyware. Gave up on SpyBot S&D some time ago - it's old, tired and slow. If they ever work the bugs out of the new version I may revisit it.
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