With this model, large, stable hand is raised without effort. Although it takes some time to adapt, (a good ten hours for me) it makes her. The mouse wheel is replaced by a rotation of the ball about the z axis. This may sound barbaric said like that, but it is done very naturally with one or two fingers.
The software is full and no more. You can set the four buttons, button combos (the bottom two simultaneously and both the top). Choose whether you want to laccélération for moving the pointer, and inertia for vertical scroll.
I found moldy media functions so I uninstalled the second app that handles all ca.
So overall this is a good trackball experience, with comfort and precision (I still keeps a mouse for nervous games of the genre fps). Aesthetics is successful. I just regret the side "light" plastic and noisy buttons.