craigb,
First, I have no desire to argue with you or anyone else.
My nephew used to use avast!, but got infected.
Avast! removed the infection with a boot-time scan,
but couldn't clean up from the infection leaving
him in a in an endless cycle of reboots.
He switched to MSE, MSE cleaned up his system.
He hasn't been infected since.
He likes social networking sites, always on them.
I'm sure you are aware of the dangers on those sites.
BTW, he still goes to the site where he was infected, but doesn't get infected now.
Tests can be and are manipulated to get the results they want.
I prefer real-world experiences.