One more thought to consider, when considering DrZogg's post. It does matter what type of user you're talking about:
1. Home
2. Small Business
3. Corporate
And therefore whom it's for, who will be using it, who will be doing the support, etc, etc. Frankly for home use, there are probably several that are safe enough. My personal favorite right now is Microsoft Security Essentials. I like Avira Antivir, but for home use, their practically constant pop-ups have been getting to be too much. I've gotten to where I'd rather risk being infected than deal with the prompts to "buy our pro version".
"But thanks be to God, which giveth us the victory through our Lord Jesus Christ." 1 Corinthians 15:57