The av-comparatives test only tests the paid for versions of AVs.
I've been following the various tests they do every three months or so, for a few years.
Top, second, and third spot rotate around regularly, often in a short period, and often with a very few percentage points separating the leaders from the also-rans.
At times I've seen Avast, or Avira in top spot, at times Norton, other times Kaspersy, Nod32, or F-secure. Point is, it's a tight game, and placement doesn't actually mean that much. Top spot moves every quarter. If not in one aspect, then another. (Scan time, false positives, prevention, removal etc.)
The important thing, though, regarding the following, is that only commercial, or paid for versions of AV's are tested.
The free version of Avast uses the same engines, (yes, engines) and database as the paid one. I'm not sure about the present, but in the past the databases and/or the effectiveness of some of the other free versions was not as good as the paid for alternatives.
So, I'm using the free one, and feel pretty protected, having not had malware for at least three years.
Last edited by Tarq57; 12th Apr 2011 at 04:21.