What is the best anti-virus?

don't you wonder what is the best anti-virus out there? well to answer that its hard mainly its just your opinion on which is the best. I think that kaspersky is the best anti-virus out there since its very easy to use, its not hard on the system and it is usually one of the first anti-virus to detect a new threat . Although one bad thing about it is the price its pretty pricey compared to other one's on the market. The best FREE anti-virus is avast well again that is just my opinion but it has a very clean and good interface and updates hourly also you can scan before windows starts up which some anti-virus's out there don't do. If you got other suggestions for anti-virus on windows,mac or linux email me a bachisawsum@googlemail.com