In short, such a purchase is almost essential for anyone who is forced to spend many hours are computer, it's the whole experience that is changed by this mouse.
It's just a shame it does not take care of the movement of the Magic Mouse from Apple, which is less ergonomic, noisier and more tiring to use and I am forced to use when I work on a Mac ...
At delivery, perfect, as usual, in the nickel package and announced possible;)