Dude, you an haxx0r your cable and get absolutly incredible speeds. Something like actual download at 10mbps, upload at 2mbps. And those are actual speeds, not just "theoretical" speeds that the companies quote you.
6.0mbps/512kbps DSL ftw.
I've never had a single speed problem on my line, except when I corrupted the actual ports at BellSouth's substation from running too many people on a CS server hosted at my house. I do have problems with my modem and router, where they have to be reset once a day though. Regardless, I'm happy with my system, and I seed torrents like nobody's business.