I was using Norton Antivirus and Internet Security 2008 and it was really good preventing treats,spyware and viruses so someome would tell it is excelent choice, but,there is always other side of the sword.I was using Vista Home Premium edition v. 32bit so as you all propably know Vista 'eats' a lot of memory,add to this some of common programs we use and you will get one really slowly resoinsive pc. So mine opinion for Norton AV is:Protection: 9/10Resources: 5/10 (less = slower)About Nod AV.I recently changed my OS to Vista Ultimate x64 edition and installed NOD.It is very nice suprise.System works much faster and Antivirus uses less memory so mine comp. get faster.Protection is also very good.If you update it on time you are going to be for sure safe from all new viruses,so mine opinion and recommendations for NOD AV:Protection 9/10 because no spyware protectionResources: 10/10Sorry for my bad English.