It works very well, mouse sensitivity is very high but probably you would adjust scrolling speed:

sudo rmmod hid_magicmouse; sudo modprobe hid_magicmouse scroll-speed=50 scroll-acceleration=1

Changing “scroll-speed” parameter try the best for you then set it permanently creating a modprobe.d config file

sudo nano /etc/modprobe.d/magicmouse.conf

options hid_magicmouse scroll-speed=50 scroll-acceleration=1

On Windows 8.1 installed via bootcamp it works out of the box

Not yet tested :)