I've tried many different packages and AVG is the boy for me, my PCs are also for business and running forums, so I need them to be clean, the only one I don't have a paid subscription on is the laptop, as I only use it for four weeks or so a year. On the laptop I run AVG free and I think it might be Sygate personal.
I wouldn't let Norton near one of my PCs and the first job I do for any of my friends when they buy a Dell PC, is remove all of the crap, including Norton.