got this a few days ago; liked the idea of a slim, sleek mouse, where the scrollwheel can (optionally) behave as a trackball. just sharing some observations:
glides better than my wireless mightymouse, feels good in my hand.
takes a second to pair after wake-from-sleep; much better than my older kensington bluetooth mouse tho.
i'm using it sometimes as a trackball; with my left hand (to give the right a rest); takes some getting used to, but works great, been using the arrow keys on my keyboard to scroll; this combination works well.
wish i could control the scroll/trackball speed (but no kensington software works with this mouse).
am trying steermouse to control tracking speed...
overall, a great investment. sometimes i use it right hand as a mouse, sometimes left hand as a trackball.
my right hand appreciates the break!
good price at buy.com; recommended!