I've been hearing a lot of good things about MSE, so it seems it has actually become really good lately.
I'm currently trying out a trial for Eset NOD32 though. I'm happy so far. Might buy it once it runs out.
Ones I would not recommend is Avast, AVG and Norton. Norton let a pretty major rootkit slip into my system a few months back and couldn't even detect it, much less do anything about it. Both Avast and AVG have destroyed my Windows installs in the past by deleting key Windows files that had become infected.
