Some facts...
Virus Bulletin is kind of an organisation who involved in standardising Anti-Virus software. You might have already heard of it.
See latest test summary. Avast have VB100 for all OSs.
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Avast plays a nice role there too.
More than everything, Avast is free. I'm sure you will say, you don't want the paid version since all important features are there in Avast.
I'm a member in Virus Bulletin for many years now and I always depend on their test results. If you really trust your AV software, they have a virus file for you to test


Worth to give a try.