Sourie very efficient and very accurate !!! Fully customizable, either standard button, keyboard shortcuts or fully modeled macro, everything is assignable to 13 buttons on this mouse Drivers are available for download on the Logitech site which is not too bad (for you buy it on Amazon, you have the net so no problems =) You can see that some find it too heavy ... Although it is heavier than the optical souries Dell first prize but it is widely bearable.
The only downside would be the life of the battery ... which is limited to 48 72h only see (at least for my use (office and video games) But this can be remedied by replacing the shield with a more powerful (which should cost a further ten euros) for absolut comfort! (Hence the 4 stars)
I would do without hesitation that choice anyway !!!