Well, I use AVG at the moment, but after reading that everyone else here is using Avast rather than AVG, that they recommend Avast over AVG and that Avast has come ahead of AVG on nearly every test carried out on them (such as detection etc) I've decided to move back to Avast. I'm not particularly bothered about how slow or fast my AV is (it's not like my rig can't handle a slightly heavy program), just as long as it protects me good.