My Mac "mighty-mouse" has been broken for some time, and found this as a cheap solution to what I thought was a similar-looking and cost-effective Mac mouse (also suitable for windows, of course)
The design itself isn't so bad, I wasn't too bothered what it looked like, as long as I can scroll up and down (since the scroll ball on my previous mouse was no longer working) access my Dashboard with the scroll button and didn't have an obvious right-click button, it would be okay.
After using it, I've found it a pain adjusting to this "rocking action", which serves as a major strain on my wrist when having to click and drag items and horizontal scroll-bars as well as select text when typing, rendering this supposed unique "ergonomic" design completely useless. The fact that the normal buttons are actually on the sides of the mouse is stupidly awkward when standard mouses have the buttons on the top for your fingers to click -- Not your palm? As for left and right click, even using this on a Windows computer, it's just as awkward.
I wasn't expecting a great deal with this product, since it was only a cheap and temporary solution until I could afford a better mouse and thought if it was good enough, I might not need replace it after all. But I'm still a little put-out with this item since I could have just purchased a cheaper dull-looking one and it would have served much more use than this one.