I always switch to the hidden admin account and just use it, no UAC to worry about. I prefer to be the captain of my own ship.
That said, I really like Bitdefender's free version. It scores top of the field. I use Eset myself, but it is not free.
That said, I really like Bitdefender's free version. It scores top of the field. I use Eset myself, but it is not free.