I spent £80 on NIS 3.0. Whenever I start up the computer it displays a whole list of error messages. Due to bad compatibily with OSX 10.4, even though this is the latest version of NIS!!!
Apart from an Antivirus the package doesn't seem to do anything that OSX doesn't do itself with its own built in firewall, and sharing protection.
I've also been told by many people including staff at the local Apple resellers that MAC's don't get viruses anyway, so there's no point spending hard earned cash on this product.
Waste of time and money!