We use AVAST, and it's so good for a while I couldn't even send emails...LOL All kidding aside, since we started using AVAST we haven't had a single issue. If a site is infected my screen goes red and an alarm goes off. It works quietly in the background.
We had Norton before and it was as useless as boobs on a boar.....LOL I had more germs from their service than if I didn't use an anti virus program at all.
I had a laptop with McAfee already on it from the factory. It messed up my hard drive somehow. I call their tech line and the guy told me to get rid of McAfee and use another program. I assume after they reviewed the recorded tape he was fired..LOL