Re: But what is the alternative?
Kaspersky ... excellent detection but it will slow your computer down, but not as much as McAfee. Also, it has a nasty habit of turning on debugging mode. When this happens, Kaspersky generates log files but never deletes older ones. When this happens, you'll quickly run out of disk space until you turn off debugging and delete the several hundred thousand log files.
I would make one additional comment to this as a Kaspersky user both at home at at a place of prior employment.
I've only ever had one big fault with the home version, and that was a pretty long time ago now. I generally find that the home anti-virus package works pretty well. I tend to stay away from teh full-on "Internet Security" thing for the same reason why I don't use crud like Norton or McAfee - I want anti-virus packages to do anti-virus things. It's why I have liked Linux in the past; each package doing one thing well rather than doing lots of things poorly (yeah, then systemd came along...)
The business version of Kaspersky, on the other hand, has the capacity to be a royal pain in the butt. Installation can be a pain and compatibility with some applications (or lack thereof) used to give my colleagues and myself regular headaches to the point where removal and replacement were the only solutions. And that wasn't too easy either.