There are many, the thing to remember is, you need to really look at the test medium before making a judgement. Then consider whats important to you!
ITW (In the Wild) is certainly pretty important, but a vast majority of the threats I have personally run into, are existing trojans and worms - some Zoo samples. Script kiddies seem to be in the habit lately, or downloading trojans off of the various VX sites, then repacking them and attempting to put them out on P2P networks.
In that case, Avast does VERY good at detecting these threats. Dos viruses should not be important to you as a windows user, so discount the dos virus test results floating around there - as with the other OS ones.
Any case, Av-Comparatives is good - just remove the results for other OS's and Dos.
http://www.av-comparatives.org/Rokop is another good site, but its in German, have your translation tools ready:
http://www.rokop-security.de/main/article.php?sid=753