I think that the mouse is not designed for Central Europeans.
The extent of my hand are also more likely to be regarded as normal:
If I take a ruler like a gun in his hand, so in the skin fold between thumb and hand using light pressure insertion of the thumb, the index finger from the base of the thumb is made 6cm long, about 11 cm long and the middle finger about 11.5 cm long , height of the hand when I share it with relaxed perpendicular to the table just 9cm. (Highest point measured hand back, not with your fingers)
Maybe you can help so the measurement of the hand to decide in advance whether what is for you.
I now stay with my Logitech Performance MX, which is at least large enough.