I've found that the combination of discs & pads are quite a big factor performance wise, certain disc/pad combinations seem to be quite poor
e.g. I've heard a lot of people have said ebc greenstuff pads are sh*te, I had greenstuff pads with ebc discs that were a
massive improvement over std new ones (put new std on as I couldn't afford the upgrade for another month and they were desperate for changing

)
Another example is, my old man was told not to use ebc red/greenstuff pads with his tarox discs as they would perform sh*t
My advice is to see what pads people say are good & perform well and find out what discs they are using with them and vice versa