going to disagree with you, piz... AVG caused/allowed a complete meltdown of my OS.
The only free AV program out there, that's worth a glass of horse piss, is 'avast!' and it's 3rd rate as it is.
Now I know the old saying, "The plural of anecdote isn't data," but for my experience the free AV programs are all completely worthless in the long run.
Hell, some even GIVE you rootkit / registry virus'.
Again, cumbersome or not, you get what you pay for.
(Your mileage may vary, offer not available in most states, past performance is not indicative of future results, have a nice day.)