I use VanBurens_cablenut_settings_version_6_ . I use the 5000/384 ccs.
But the biggest improvement comes when I install Kaspersky Internet Service 6.0.
My download speed will go from 7500-7900, to 8300-8700 when I install Kaspersky Internet Service 6.0. Why I don't know.
Download a copy of KIS 6.0 and tell me what your results are. They have a trial you try.
My download speeds stay pretty much the same, once in a while it will drop some but not much.
My download speeds stay pretty much the same as time go's by