I have been pleasantly suprised with this product. I have previously been running a combination of Kaspersky and Ad-Aware to protect my system, but upon my lisence running out for the former i decided to give this a go. It runs on very little processing power (helpfull as my laptop is starting to get on) and is very easy to navigate, something which kaspersky does seem to lack in some ways.
I did find that it missed some of the more in depth aspects that kaspersky provides, but the other features in BitDefender like health check did make up for things.
Overall i still feel the need to run Ad-Aware to keep my system fully secure, but I do prefer to be slightly more careful. Just avoid the internet security package, it really doesn't match up to the anti-virus suite.
For the price it is an amazing peice of software, definatly recommended, especially if your computer system is not top of the range.