I do use one. But I'm amussed by the people that find my AV say this file has a virus, thus it must have a virus.
AV programs are normal programs like the rest. They may have bugs and for sure won't work perfect.
As frail as the AV programs are, what other solution is out there that is better? Script blocks, ad blocks works for web browser. If you donwload a SW from a source you can't trust to 100% (and it exit none source, expect you that you can trust to 100%) then you must decide.
Use no AV and decide that the last few per cent are acceptable. Find the last few per cent inacceptable, then you need another part of SW to close the gap. None SW, thus the result can be lower with the security SW than without it. But no one can give you this numbers, so this is much more of a religious war than anything other.
A scriptblocker and the built-in virus scanner from Microsoft are completely sufficient. Almost 100% of all attacks on the PC in the web browser are carried out via Javascript. For almost 10 years now, I have only used script blockers such as umatrix, Windows Defender (which was still called that back then) and, of course, my brain. I have never had any problems with hacked accounts or abnormalities in online banking, nor have I observed any strange behaviour on the PC.
The problem with all the third-party virus scanners is the engine of the virus scanner itself. The definitions may be up to date, but the engine is usually hopelessly outdated. And this is exactly where the programmers of the malware come in. A fully patched Windows is not designed for additional software to do mischief with it. Just think of it this way: by installing the virus scanner, you close an open window in your OS, but blow a huge hole in another wall.
And that's exactly the advantage of the virus scanner from MS, it was developed directly to fit cleanly into the OS, as opposed to the hodgepodge that additional software can cause.
