Don't use AVG, the loggingserver.exe hogs ALL of your bandwidth for a good hour and a half as it checks for updates every 24 hours. Then when you uninstall AVG, a ton of junk is left behind, including the loggingserver.exe. My computer still isn't clean after having that monster on it.

I use both malwarebytes and avast and I never had any issues virus related. To be honest as long as you are careful you don't have to have one. But if you really need one I suggest the setup mentioned above.

Who is we?

Microsoft security essentials is the one i think I have on my laptop. No viruses so far, and that laptop is from about 2008 :D

1st line of defense: common sense

2nd: avast

and if I suspect anything slipped past, I occasionally run mbam

I don't at all notice a slowdown (at least, not nearly as much as norton) and so far I haven't had any issues.

MSE is pretty much accepted as being the "lightest weight" on the hardware/software system. Since it's the second line of defense as TheWalkingGeek said, I use MSE. It's also convenient because it's more or less entirely hands-off and produces very few false positives.

But it looks like its protection might be lacking somewhat upon review of some third party sites - and it may or may not be the best for performance either. Arrr, I will need to reconsider soon.

This article shows where to find third party analysis of AV performance in a depth that we'd never be able to duplicate: http://www.howtogeek.com/129624/4-places-to-find-up-to-date-antivirus-test-results-online-2/ So, given that, why is anyone on PCP going to review AV again? Really?