I have a number of outdated systems, mainly running windows XP, which ran Nod32 2.7 brilliantly, until Eset decided to quit supporting that version with updates some time ago. I have switched to Avast! Free for the time being, as AV-comparitives shows that it's relatively similar in speed, performance and quality. However, I have always had good exp. with Nod32 and would like to try it again. In the meantime, version 3, 4 and 5 have emerged and I'm now a bit confused which to choose. Can someone shed some experience/light on this matter? Thank you.