My last two attempts to use the BT speedtester have shown download speeds of 7Mbps (yesterday) and 4Mbps (today). Running speedtest.net immediately afterwards gave about 37Mbps! What is going on here?
There's a thread I started on this very subject a couple of days ago.
Speedtest.net or BTspeedtest
I've had pretty well an indentical experience and have had some interesting replies already