If you believe your mac needs antivirus protection I think Intego's Virusbarrier is a good albeit a little expensive solution.
It works just like advertised and updates come at least once a week. It is very easy/intuitive to use and almost never crashes. If you're into photos or video on a pro basis you should exclude the drives with the raw material from real-time scanning to avoid a drop in data transfer rates. It's better to run VB on all your drives once every couple of weeks (months?) than to have its real-time scanner monitoring all of them constantly.

I can only give you my opinion on European customer support: they are friendly, helpful and even generous. Don't hesitate to contact them.

Personally, I must say I find the price of the app and the virus definitions a bit too expensive. Maybe Intego could reconsider their price policy. A noticable drop in prices could eventually convince many more customers to buy their products.

One thing, however, that is bothering me is that they are very very slow to implement new features requested by customers. For example, I don't see why Virusbarrier still has no option to close automatically after it completed an on-demand scan of a file started from the Finder's context menu. A price drop and open ears to customers' request would raise this product to 5 stars.