And also to consider BD as a fortress, is maybe putting to much confidence in a AV and maybe letting your guard down a bit?
Here I will explain a bit what I understand by BD as a fortress.
Because BD hasn't had any major setbacks for years and has been a leader for years. For comparison, I'm leaving out Kasperksy because I don't remember when it got banned.
In most tests that you can see online, BD is either first or loses slightly to the best in a given test. But as a rule, even if it gives up on something or does worse than expected, it still usually did better than the rest.
So they use it, you feel like you're using a fortress and you won't install anything better on your computer.
However, BD stability was always a disaster. Something was always not working. Sometimes it blocked something. This is the only AV I had where I had to uninstall and reinstall it.
But
@Shadowra test gave me something to think about. Eset finally made up for its "losses" and finally everything works as it should.
Based on my experience of putting it into my relative's PC, who has zero idea about security and just barely can browse the web, Avast might be your best choice.
No thanks. I used to have it. It's just problems. Avast doesn't trust me. Besides, it always made a mess in the system. And now it's part of the Norton family. No thanks, I don't want it
I agree in a sense with this, but BD used to be really bad with its pop up notifications, but they have since silenced most of those except for the mandatory suspicious connection pop ups.
I've been using Bitdefender for over a year and I don't remember many notifications.
When I used to have Eset and configured it on Fortress, it kept getting something wrong. Constantly some notifications. It was annoying. And very sensitive to everything. Sometimes you had the impression that it was attacking you with some false positives. You constantly had to add something to the exceptions.
There was a way out. Change the settings, disable some, such as potentially dangerous applications, etc. But then why do you need AV, if you have to disable certain functions to have greater comfort of use at the expense of security.
Not to mention that after installing Eset it has a lot of settings and you can click away until you die.
Fsecure or Bitdefender look different. You install it, quickly configure it because there are very few settings compared to Eset and that's it. And then they only pop up when they catch something, detect something, etc. And that's how Eset should work.
But.....
I've had Eset Smart Security Premium for 5 days. After installing, I configured it, checked most of the options, etc. And for now it sits quietly. Only when it catches something, it speaks up. For now, I feel a huge progress. Unfortunately, for some it is a disadvantage and for others an advantage - configuring all the options takes a very long time, because there are a lot of settings. And the readability of these settings is also not clear, because logically you look for some in a different place than they are.
After 5 days. Eset is lighter on the computer than Fsecure. And you can feel it. Bitdefender was heavier than Fsecure. Eset scans the entire computer the fastest of all (Bitdefender was the slowest).
On Eset, my internet runs faster, even with HTTPS scanning enabled. Its scanner is very fast. In this respect, the slowest internet went for me under Fsecure and the Fsecure plugin for Firefox with a lot of tabs enabled could crack.
Another advantage, similarly to BD, scans zipped/rar files downloaded via www, which Fsecure did not do.
For now, what annoys me about Eset.
1. Search results only mark in Google search engine. For example, it is not in DuckDuckGo. BD and Fsecure had it in each.
2. Secure browser. Frame is annoying when watching YouTube in full screen
3. Disabling the frame while browsing the Internet in the browser disables the frame. But there is no option to enable it again. You have to open a new browser window (or I did not find such an option)
Anyway. After 5 days, a very big plus. Stable. It works lightly, you do not feel its presence on the computer. Set to "max" and it sits quietly and does not irritate.
Another advantage of Eset in my case. I am from Poland. Eset in Poland in the city of Krakow has its research and development center. In Poland, it has a very good reputation, because it is one, if not the only AV that recognizes various threats that can be found in Poland the fastest.
For now, it is very good. After 30 days of the trial version, I will install Bitdefender for comparison and see which one will suit me better in terms of use. Which one is and will be better in terms of detecting all threats, I will probably watch a few more tests on the Internet

There is still the matter of what prices Eset and Bitdefender will want and which and until when each of them will support Windows 10.
And I expect more Eset vs Bitdefender comparison tests. I would like to know if the above test is just Eset's luck or if BD actually has a worthy or better rival
@Shadowra - we are waiting for more tests
Regards