"It's designed for palm grippers, not for claw or fingertip grippers (it's both too big and too slippery for these grips)."
Maybe if you have tiny hands. It's pretty much the same size as the older Roccat Kone mice. If you have big hands or even just long fingers like mine they're no good at all for a palm grip. Nobody makes a gaming mouse that's big enough for a palm grip with big hands.
If I put my palm on the back of one of my old Roccat Kone mice (I have 2 of them) my fingers hang more than an inch over front of the mouse and I have to curl my thumb back to use the side buttons. I'm forced to use a claw grip even though I much prefer a palm grip but at least that's better than fingertip grip. I have yet to see a gaming mouse that isn't either too small or too heavy to use with a fingertip grip.
Please learn to take into account that not everyone has small hands before making proclamations about what mouse is suitable for what grip. Your mouse reviews would be greatly improved if you took hand size into consideration and maybe even try asking someone with large hands what he thinks.