I have never really had problems with Norton Antivirus. I have used it for many years now, both at home and at work. All of our offshore computers, probably in the region of 100 PCs, used it, essentially problem free, in a setting where remoteness calls for reliability. I also noticed that many of the oil companies used it offshore too.
I have been running Norton 360 on this laptop for almost 2 years now, problem free.