sbiddle:bisr: I can peak at 30mbits (not bytes, I get 2.2 MegaBytes) per second on my ADSL 2 connection. Seen it with my own two eyes in dd-wrt. And I live near Orewa.
It's simply not possible.
ADSL2+ can offer a maximum theoretical downstream throughput of 24Mbps before all overheads are taken into effect. This means you're typically limited to around 20 - Mbps depending on noise margin on a perfect 24Mbps sync rate (virtually impossible in the real world unless you're connected to a DSLAM), or slightly less if Annex M is used.
Okay I accept that it's possible with the signal delay in measuring the packets coming in where dd-wrt reads a blockage which creates excess flow as a spike in the throughput would result in my misinterpreting the data. Also I think in my brain I have calculated the ratio between bits and bytes backwards and this has given me 'tinted glasses' because when I go back to dd-wrt Iright now it's 18-19 Mbps and 2.2MBps and I am getting it right now as I type this.