I use F-Secure! heh.zhoominator said:F-Secure. Got a 4 year contract with my laptop and have only had one issue in the last 2 1/2 years, which was simply sorted because I had backed-up all of my files so restoring it all was pretty straightforward.
I have no idea how it compares to others because nobody else I know uses F-Secure.
It can be a bit more heavy on the resource hogging than some other antivirus-programs, but what I have seen working with it, it's quite effective. Haven't had a problem in years.