echo whites are not up to anything, not even on a smooth rim, ive used yellows (they didnt last for me very long), blues (which were incredible), tnn lgms (worked for a bit, two pairs of them) if anything id go for rockman blues in cnc backings, defiantly best pads ive ever had, and not problems, when i bought my bike, they came on, and the guy said he had had the same pads on for over a year, and they are still on my bike now with at least a quarter pad material left, and still with lots of noise, i have some new rockman blues waiting to be put on once these have gone, but honestly, if you have the money and you want cnc backings, defo rockmans or cousts