Definitely agree with the Nissin vote (after all, they made the calipers so should know a thing or two!).
I just had to bin my last set of Nissin pads; they lasted well, but a stuck piston caused one pad to wear rather unevenly towards the end, which accelerated their demise.
I now have a set of Carbone Lorraine pads with which I've previously had good experiences on other bikes.
But... well... they just don't seem as responsive

They're still good stopping material, don't get me wrong, it's just that they don't seem to have the same instant confidence-inspiring bite.
I miss the Nissin pads!