I used Avast, it was ok. I used Norton for years, but tired of the large resource use, had AVG too. Same problems, switched to MSE, turned out to be the best freeware provided by microsoft to complement thier software. Then I upgraded my service provider, which gave me McAfee Security Center for free, and having thoroughly vetted it, I can say that it works very nicely, lovin' itI went to Avast years ago. Got fed up with Norton and Mcaffee and their bloat. I tried AVG and ran into a problem, it froze PC if mouse went over a file with SP2 for XP or the row of files and spent several minutes scanning it. Their forum seemed a bit snooty and unhelpful so I switched to Avast.
Joe
Same here.for me, I'll happily stay, as I have for years, w/ MSE.