I have been using Kaspersky for a few years, and have been liking it. But they have an aggravating habit of sending emails that your license is about to expire, when the screen shows you have 150 odd days remaining. I have been through this before, you have to find your activation code, fiddle around with that, and they say...ok!
I got tired of that crap, dumped them last night and installed NOD32 from ESET. I have heard good things about it. So far, so good.