I bought Roccat Savu 2 weeks ago and just couldn't get used to it because my hand is too big.
You are not going to feel comfortable if you prefer full palm grip, however, if your hands are smaller, this mouse must be totally great, its sides and top feel amazing to touch, it's really solid built, I liked the way the buttons respond when I pressed them. I didn't like the laser sensor because I've always used optical mice but I think it's just a matter of habit.
Roccat Kone is pretty much similar speaking of measurements which is the main reason I didn't look into buying it.
After some research I got the Steelseries Rival which completely satisfies me.