What is your opinion of AVAST free anti-virus?

[Egnever]

5. Better than nothing but way too invasive for my taste.

From https://selabs.uk/en/reports/consumers

Avast Free Antivirus was the least effective product
in this test, although its performance was still strong
enough to earn an AA award. It stopped a fair few of
the targeted attacks and all of the public web threats,
but its slightly less accurate handling of legitimate
software pushed it to the bottom of the table.

Microsoft Security Essentials was the strongest
free product in the test. It was compromised five
times by the targeted attacks but protected against
all but two of the web-based attacks. It only blocked
one legitimate application.

In my experience combining windows defender and occasional scans with the free version of malware bytes you cover yourself pretty well.

PCMAG is a bunch of hacks in my opinion btw.