Went from a GPX1 to this and had fears of the holes being a problem, but honestly they feel much better for my grip my hand sits slightly in the grooves so I have perfect grip.
I also doubted the material and thought it would bend/crack, but it's sturdier feeling than the GPX1 and so much more lighter feeling 20grams isn't much, but you can really feel the lightness.
Perfect mouse and battery charge lasts longer than 7days on 1k Hz.