My down/upload speeds have both tested poorly in recent days. I'm on Pipex Extreme3 I think on 8mb like you. My download speed is better than yours and my upload similar. Both have deteriorated though.
i have had problems with speed in the past and i went through having bt engineers looking at it my prob was i had good speed during the day but at 1630 to 2300 it was bad. as pipex uses tiscalli as a backbone i think that the problem is with them they throttle the speed at night times all i can say is keep complaining and test your speeds at various times of the day.