Just for the hell of it I'm trying a trial version of Avast! Internet Security. It has little or no discernible effect on my Windows7 64 bit system. Boot-up is quick and web filters and virtualisation have minimal effect, too. I like that it can be set to scan SSL emails - the method is interesting in that you have to tell Avast the settings for your SSL email and then set your mail client to work non-SSL. Avast! scans in and out in non-SSL mode & then actually sends or receives your mail in SSL mode - cool. (I use Thunderbird with Gmail's POP & SMTP servers) If I was in the habit of paying for software, I would be very tempted by this offering!