So far, I've used Norton (unimpressed), MCAFEE (bloated and slooowwwww), and currently have ETRUST, and I absolutely love it. I can't even tell it is on my system. I have the Security Suite, and I have no problems whatsoever. I've played with AVG (free version), and didn't like it too well. I may look at NOD and AVIRA, one of these days, but not in any hurry at the moment. No matter which security suite I have, I will always be running Spybot S & D, with Teatimer, and at least one other.