To answer your question...no, it's been proven time and again to not have any real effect. Why? Well cos most apps don't use QoS, so it goes unused. And the easier way to disable it altogether, is to go to properties for your netowrk connection and just remove QoS from the list; this also reduceds the overhead for that connection which is even better. The only app that I can think of off the top of my head that would use QoS, or benefit from it, is a VoIP app (like Skype for example); but again, the app would have to be created to take advantage of QoS to see any difference.
On another note, the QoS Packet Scheduler is not used to make sure you have updates, it is used to determine how many packets each connection receives at any given time. So if say you have 3 apps running that using bandwidth, and 1 of them is a VoIP app that can use QoS, it would be guaranteed x% of your bandiwdth every time it requested it to get its packets in and/or out, and simply fight up with the other 2 apps for the remaining percentage.
More info on Quality of Service:
http://www.answers.com/topic/packet-scheduler-1http://www.answers.com/topic/quality-of-service
