I tried Kaspersky. It wouldn't install on one of my machines because it didn't like the Comodo firewall and insisted I uninstall it. No chance. It wouldn't install on another (that was using ZoneAlarm) telling me there was an error 1304 and objecting to a driver file in \windows\system32\drivers (a ZoneAlarm file
IIRC) ...... and it installed on a 3rd machine, wouldn't uninstall and killed that Windows installation.
A lot of people use it and love it, including some friends. But
after having paid for that licence I ended up chucking it in the bin, because it's FAR too temperamental about what it will and won't work with.
I
might be prepared to use their suite if I was willing to use their firewall, but I'm content with my current firewall products and I'm not messing about problem-solving driver clashes or uninstalling firewalls just to use their stand-alone AV module.
So I use a mix of NOD32 (top product
IMHO, but not free), Avast, Avira Personal and AVG free.