if you're after someone elses observation then you can have mine, i've used a few different pads in the past and on a smooth rim this is definitely 1 that stands out to work best, i would say as good as my zoo pads on EX721 CD smooth with plenty tar. also it still bites better than my heatsink reds on a very sharp grind on dob rim, pretty insane, just the noise which i don't really like but thats preference. probably from bmx/skate mag photo shoots? they use mk buszy quite often... the marble is pretty unique in itself anyway. steve