I have never tried it. I never had any major issues with it so I just stuck with Norton. Do you recommend Microsoft security essentials over it? Or at least equally as effective?
I use it. It seems to be reasonably effective. On acouple of occasions it has caught malware links.
It gets updated as needed as a byproduct of microsoft update. It will also update daily if needed or instantly if a suspicious condition should occur.
I figure MS knows what they are doing in this arena.