I will always go with Avira Internet Security Suite.I think it's is the best antivirus available right now. I am very much experienced with several antiviruses like kaspersky,zonealarm,avast,norton,avg. Kaspersky always catches a false detection viruses which is not good when you are running some keygens which is not infected.
One more think about this kaspersky it always slow down your computer.
Avira is always best whether in terms of catching highly infected viruses or low infected viruses and it doesn't slow down your computer.