I've tried alot of different security programs, MacAfee, Panda, Norman, Norton, F-Secure and so on. NOD32 is the one that I like the most, it provides a very safe and easy-to-use system to a very, hehehe
, low cost and low CPU usage.
Norman antivirus is, in my opinion, a VERY unstable security system and should not be used by anyone anytime. The company providing it seemes to be very unserious and It's not a recomandation.