well i may hate PC Guard as much as i do the Tax Man, and it's as resource efficient as a 50 year old coke fired power station. But it's safer than having nothing.
But then again, there are loads of free alternatives that have been mentioned here, that are far more reliable, stable, use as much system resources as my brain after 8 pints of beer
Ashampoo and avast, currently using, always get a thumbs up. Daily updates to avast also
))
I do use comodo, but on my 64bit system, it works a treat on that.