Most people think only the sender can manipulate how fast data is sent, they forget the receiver controls the receive window.
e.g. use a ftp client that can set the receive window, set it something small like 4k and watch your tiny download speeds
For this reason a cheap and easy method of QoS can be to disable auto tcp tuning on vista+, which caps the receive window to 64k. That will generally give you much better latency whilst downloading on that windows client although it will also cap speeds when the latency is high enough from the server.
Auto tuning on highlyrestricted caps it to 256k, I used to run like that for quite a long while as it still allows highish speeds on latency ranges up to about 100-150ms.
Restricted and normal will cap it at 2mb, experimental raises the cap to 16mb.