I've been using Avast's free version for a couple of years now without issues. The only time I've had to re-install is when they totally overhaul the entire engine.

I actually use microsoft security essentials. I have been infected with a virus only once and that came from messenger because my gf click a link which came from her friend... Best antivirus solution in my experience is common sense

Do not get me wrong, but I read some "pros" opinions, that this "idea" from MS is good but for now it is too early to use MS SE as good protection. There is still a long way for MS here to learn and to "get it good". Yes, some of "pros" are using it but they say it requires lots of "home made" patches and hotfixes.

Also, I agree, that best protection is just common sense. No av program could be compared to that.

The problem with common sense is that it's not too common. :)

As that motivation I linked said: it' a super power...

A lot of the pirated copies were at companies or charities (so the enterprise features may have been in use, dunno), from the article I read. The cool thing was how the Avast! company handled it. They watched the spread out of interest and when done they just send offers out for people to buy the actual product and support them. I do not recall if the offers included a discount. I know a few people on here find that idea abhorrent but I think it's a great idea.