Iain, this is mine with
PlusNet.
Downstream 1841 Kbps (230.1 KB/sec) 1988 Kbps (inc. overheads)
Upstream 242 Kbps (30.3 KB/sec) 261 Kbps (inc. overheads)
It will be a bit variable during the day though depending on the ISP. As the speed gets higher you are more susceptible to second-by-second changes in network congestion. To get the maximum possible speed reading, test in the middle of the night!
In Dr TCP, MTU should normally be set to 1500, RWIN to 38400 is plenty.
If you are confident in editing the registry I highly recommend these two registry tweaks (assuming you have Windows 2000 or XP):
Maximum simultaneous connections in IE (drastically increases speed of loading of webpages)
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings
Set MaxConnectionsPer1_0Server and MaxConnectionsPerServer to 16 decimal.
RWIN (does what Dr TCP does):
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters
Set TcpWindowSize to 38400