I used AVG free for a couple of years and my company now sends it out on the new units instead of Norton. I upgraded to AVG 8.0 this past summer just to be safe, Trojan Horse Anti Virus 2009 Pro got by it about a month ago and caused me all kid of hell. I had to buy live support from AVG for $129 to get it off of my computer. They (AVG) logged in on my unit and for three hours they ran test, deleted items and cleaned files, I haven't had a problem since (keeping my fingers crossed)
Dell try to get rid of it and ended up telling me I had to do a complete re-install to where my computer was on day 1. I had to many work files to do this, the $129 was worth it to me.