i found a guy on fleabay that will sell me red stuff pads and ebc turbo groove discs for £150 delivered all brand new and for the st170.
the discs were on a make best offer which came to £110.
thats what i'm going to go for but i can't comment on the performance, but i'm willing to bet that it would be a noticable difference/improvement.
pm me if you want his info.
dan.