Very interesting. I've run powerstop on all my cars as do dozens of others I know and they are all dead quiet. I have the exact opposite experience as you (and so do everyone else I know in person who have actually tried both brands) it's always been hawk is noisy, powerstop is quiet and the...
What powerstop pads did you have? Powerstop pads are dead quiet. You can't hear them at all and they don't dust. The hawk pads are pretty noisy and they dust much worse. Z23 and z26 make 0 noise maybe you got a bad batch or you installed them wrong or you are confusing them with the hawk pads...
Having done extensive research myself on the forums I've found (this applies TO STREET USE) powerstop z26 pads are the best, no noise no dust (OEM pads have heavy dust) and z26 and z23 are the same compound the only change is metal backing plate on the z26. Initial bite with z26 aren't as sharp...