Ok, I complained to Orange (twice). Had to insist that I talk to a supervisor, then the supervisors manager (Rotherham). In parallel I lodged a complaint with the ISPA.
I had an outage for a month PPP server down then lost sync.,after the usual runaround I was reconnected.
When reconnected I had the 6Mbit connection(well it synced around that !) ...
My experience
My Exchange was LLU'd 26/02/07 (Chandlers Ford)
After this speeds were about 2000 - 2700 kb/s
Syncing around 5000 - 6200 kb/s
This started to slow down to around 500 by 07/03/07 some ...