Your upload is also throttled down to 256Kbps, I've seen people with only 4Mbps with Be* still able to get a good upload ~1.1Mbps.
Either way, I have to say that I sync at 20Mbps/1.3Mbps with Be*, no throttling, line length is ~1.4km, you just need to be fortunate to live near the telephone exchange.
I'll have to be honest though, not really many reasons to be downloading at that speed, current steaming services like youtube or BBC iplayer are no where near it (unless someone can point me to another service that has super quality), things like drivers from MS, Nvidia, ATI, Logitech etc... do thunder down at 2MB/sec but you're done in minutes...