I have used both. AVG was easier in the setup and has a nicer interface and controls. I prefer AVG . It is trusted by more users than Avast (dunno why). However the truth is Avast has better detection than AVG. (slightly better) But no Antivirus is 100% good. There is always stuff Avast won't catch but AVG will or AVG won't catch but Avast will. Try Avira as well. Most people say Avira uses less system resources than Avast.
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