Weird, I had 2 sets of plaz and both of them were very good ! on a grind of course, even when the grind was dead they were still offering a great performance ! You could try to put a fresh grind, put your pads on, and go down a hill holiding the brake a little bit, they will do a lot of noise, but I did that with mine and after that they were working very well ! make sure you don't hold your brake too long because the pads will surely worn out fater than usual