I too have experimented with all kinds of anti-virus software but for me it would be a tie between Avast and AVG. They basically seem to have same features. Although I've used (installed on many computers in an organization) AVG the most and many people whom I talk to also prefer AVG a lot so I guess AVG would probably win my vote it I would only have to pick one. Although it came in 10th place when PC World rated Anti viruses I still think it is pretty good.