Those types of programs, usually regarded as high end or perhaps esoteric because of their sophistication and relative rarety in the home market, can be very effective in securing a computer.

They just take a bit of tweaking, at least initially, to set up and get running. Once they've been taught to recognize all the programs you have installed on your PC then usually the only time you need to deal with it after that is when a new program is installed either by you or a virus/trojan/etc.

Still, they don't replace a good a/v or spyware scanner. I feel it's best not to download or run a program as a first line of defense rather than rely soley on a program that won't stop it until it starts to run.

Working side by side is a more effective strategy.