I've been happily using Avira for years (on Windows 7). It doesn't bother me other than sometime showing a "buy me" pop up ad when it updates itself (usually when I start the PC the first time during a day), but the popup can be closed easily or goes away by itself, so it doesn't really bother me. And if it did, I guess I could pay for Avira to get the premium version.

I don't feel I am getting lots of false positives like some seem to be complaining about their antivirus, like GOG games having malware according to their antivirus etc. So in that department Avira seems fine too, not much of false positives as far as I can remember.

I have no real idea how well Avira detects malware (compared to other antivirus), but I trust it, and use sense when go to internets. I did get infected once (or actually it was my wife), many many years ago, by some "Security Sphere 2013" malware, even though I had Avira running, so yeah it is not perfect either, but I presume no antivirus can be 100% perfect.

At some point I did use Windows 7 default MS antivirus, but I switched back to Avira when I read some of the reports that MS antivirus had the lowest detection rate of all antivirus programs. Not sure if that has changed since.

At some point I also tried out some of the other common (free) antivirus, I'm sure Avast was one of them, but there were certain things that irritated with them so I went back to Avira. Like some antivirus (could have been Avast?) required at least back then to register to their web site once a year with your email, even if you were using the free version. Avira has always felt more "hands-off" or "fire and forget", ie. you install it once and can forget about it after that. It updates itself when it needs to, sometimes shows you the "buy me!" pop-up, but that's all. No actively needing to register once a year etc. That was quite important to me as I was also installing stuff for some non-techie types, it was important that their antivirus would not require extra actions from them.

Why would you not want to use the firewall to allow internet access only to the programs you're comfortable with having internet access? I have set as default to be asked when a new program wants to access the internet, and then I decide if I grant for it permanent, temporary or deny access. I have no need for the Nvidia telemetry-laden drivers to go on internet.

The free versions lack a lot of features, it won't protect you if you access and infected site, I guess.

I use a separate firewall.

The one in Kaspersky might be better? I don't know, never bothered trying a standalone firewall since the one included did exactly what I wanted. Plus, it eliminates another running program. Like I said before, try a trial version first, and then decide for yourself.

No. I'm for my firewall I'm simply using Windows Firewall at the moment. All you have to do is block outgoing connections by default and create exception rules for programs that you want. That (and router's NAT) is all you really need.

I am preferring Webroot now due to it's very low footprint and high speed. I think it is the AV I have used which has the best performance and least system impact I have used.

Been using Avira and malwarebytes for some years now. One ad at startup, wouldn't know it's there otherwise.

Kaspersky is a good one.
However, with windows 10, sometimes after a feature update the system disabled it and enabled the built-in one.
A few restarts coupled with re-installs at time fixed it as far as I remember.

Also the free version won't include the real time protection elements in most paid AV suites. So I think getting a paid version will be better.
Also Malwarebytes Free version is a good scanner I have heard and works nicely alongside a few other AV suites.

^
This.

I absolutely can't stand anti-virus and I thought the inability to turn off Defender in Windows 10 was going to be a big issue but it's actually not intrusive at all beyond the occasional pop up asking to update definitions.

I haven't used anything else for years, not since I realised AVG was actually slowing my computer down more than any of the viruses it might be preventing...

If I have any worry I've actually been infected with something (weird behaviour or clicked a link I probably shouldn't have) I use Malware Bytes to scan and remove anything.

^I too second this. AFAIK all AV products have been Zero-Day'd in the past and became a threat themselves, none of them prevents a brand new attack vector in the first few hours after it's know. There's a reason many security experts call AV software "snake oil".

I wouldn't go as far as that, because I would never let the machine of an inexperienced user run without AV, and I use Malwarebytes (free) when I suspect there might be something off, or I get potentially dangerous media. The nice thing about Malwarebytes is that it also finds and kills "unwanted software" (like - ad-ware) which often comes with "free" software installers and which is ignored by many AV programs.

For an experienced user "brain" should be the best AV solution.

In a (past) company environment with a CEO that clicked everything that popped up in his inbox (talking about "brain"...) I had good experiences with Kapersky (paid, of course) which always managed to curb the threats and prevented spreading on the network.

I have been using Eset for 10+ years and it just works, it cost me about $10/year and that's with the firewall. You don't really notice it and it don't use much resources which was the main reason for me to use it compared to other ones out there. I have tried most of the free ones and some paid ones but kept coming back to Eset. Last time I checked Eset had a trial version you can use for a month or so, if you like it buy it otherwise try something else.

F-Secure.

Well, for free , I find that Avira it the best balance between protection and cpu usage.

Kaspersky is the best, they first write a virus, release it in the wild, then they come with the AV for it. So if you want to continue financing FSB (modern day KGB), go get it.
Anyway I'm using the Windows built-in one and haven't seen a virus in years.

Oh, no, Putin writes all the viruses... bare-chested. On horseback... In the Siberian tundra... In Winter.