I tried HH pads on my California 1100 with soft cast iron rotors and it did wear those quickly.
But never seen wear on stainless rotors.
From what I had read about HH on the EBC site and your answer here is why I thought HH would be hard on the rotor. I assumed that it was ALL types of rotors. Now I know that it's fine for stainless!!
Slowly but shurely I'm getting this bike sorted out!!
Tom