sbiddle: A master filter will improve your overall xDSL and may improve your download speed but won't make any difference at all to your upload speed.
Changing ISP also won't make any difference to your upload speed.
There is still some room for improvement on upload, but yes we are really only talking 50-100k. I have seen good ADSL2+ connections hit the mid 900s k for upstream (speedtest results).




