I've actually filed the edges of my old G3 because it got so bad. And I've given it new gliding skates. I just don't get it why is it so hard to make the mouse "belly" arched everywhere but where gliding skates are (and the sensor). Or if they can make a sensor which allows slightly higher placement. The gliding smoothness would be so much better. I mean, I had to toss out all the weights from my G502 because belly itself is adding more resistance than I want. I like the silky smooth texture of clothed mouse mats opposed to cold and gritty feeling metal ones.