is to ask this question in our Spyware, viruses and security forum.
You might want to say why you are considering this. For my part I tend to go with the flow and accept the general consensus that having more than one anti-virus running at the same time may slow down my system. It sort of makes sense to me.
As data is received into my system from whatever source it is checked by my firewall, my anti-virus, and my anti-spyware. I am sure all that slows down my system but only marginally. I don't want to make it worse by having two AV's working against each other at the same time, attempting to check the same data.
Whilst no single AV will catch all known viruses immediately, (developers have to update their definitions), keeping the anti-virus utility up to date as well as using sensible surfing habits and email procedures considerably reduces any risk.
That doesn't mean to say that you cannot have more than one AV on a system. But the 2nd one should be used only as a backup manual scanner and not running in the background.
But anyway, enough of me. Go see what the experts in the Virus forum think, 
Mark
i really am wondering: I'm using AVG-AntiVirus Free-Edition, and I'm really honestly wondering (any person who can answer this question for me, please do), would ThreatFire-AntiVirus work[/coexist] along with my AVG-AntiVirus Free-Edition? (considering everything I have heard about "don't install multiple anti-virus programs on your computer, because they will clash with each other"; her is one classic example: Norton AntiVirus installed on the same computer as MacAfee, AT THE SAME TIME, or, vice-versa; MacAfee installed on the same computer as Norton AntiVirus).
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