They are all different and all have their supporters and detractors.
I used AVG Free for years without problem, but on this new system I am using ZoneAlarm's combined firewall and anti-virus. Again no problem with this one.
I would guess that your question will produce a range of replies, so at the end of the day the choice is yours and if you are satisfied with your current AV, then is there a need to change?
What I would say is that no anti-virus scanner will find all malware nowadays, and we have to supplement our security with other anti-malware scanners, like Malwarebytes Anti-malware, or SUPERAntispware, or similar.
I hope that helps.
Mark
Just wondering what the latest opinion is on best antivirus software. I still have AVG free- is there any real advantage to the paid version?

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