Recently I have bought the Linksys E4200 router. I have found that while setting the QoS enabled which is supposed to level the network traffic but my internet slows down. For example when downloading any large file (lets say about 200 Mb) with QoS enabled, it use to take around 4 to 5 hours to complete, whereas same gets complete in 8 to 10 minutes if QoS is disabled. Another example I can say is streaming online videos. I just canít stream online videos including YouTube. It always remain buffering unless I disable QoS WMM setting.