NSS Labs warns companies for the virus scanners by Panda Security and AVG, they should not use these virus scanners according to NSS Labs. They performed a test monitoring how fast virus scanners block malicious websites. Especially Panda Security required a lot of time to accomplish this. The average time for a virus scanner to block such a website is 45 hours, however the Spaniards needed 90 hours to do so. AVG managed to do so in 71 hours. The best virus scanner required 5 hours. They also looked at the 'block rate', they speed of blocking a malicious website. The best virus scanner blocked only 60%, but AVG, Panda and Eset scored less than 44%.
The tests by NSS Labs are according to sum controversial and the research is downloadable at the fee of 500 dollar.