I haven't tried system works because of problems I have had with norton anti-virus professional. I went with the antivirus software from grisoft and it catches things that norton missed (it has saved me more than once from viruses). Also zone alarm pro is the firewall I use. The problem I had with norton is that there were some software conflicts (or so it seems) with other stuff I had installed. I had to many problems with my computer that seemed to resolve after I uninstalled Norton. Seeing Norton came with two licenses I do run it on my other computer (that doesn't have half the programs on my main computer) - but after my subscription runs out for updates, I'm not renewing it.