You're right. Avast is excellent. I use both, as I just purchased a laptop for travel photos on long trips.
I also like the interesting interface on Avast, but I would be hard pressed to choose between them. AVG 7 is also an excellent choice.
Haven't found anything to complain about on either program.
I used to use AVG bacause its good and its free, but I think AVAST might be better and its free.

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