.. Works like a mouse!

Correct assembly; the upper part (the part with buttons) seems a little fragile; but the whole is good. The mouse will certainly be a little / too small for large hands in case of prolonged labor. Ships 2 batteries and has a switch to turn off the bluetooth. Automatic connection to PC in seconds, within the reach of anyone. By cons I have put many hours figuring out how to keep Windows explain to the active BT connection and avoid disconnections whenever the mouse remained motionless 5s (and 2-3S to reconnect ... a hassle and like to smash this poor mouse that had nothing to do - the problem is Windows power saving system). The mouse works fine, precise enough for my office / pictures need, and runs on various problem-free surfaces (including the bed sheets ^^). I like to keep a free USB port and not have to ask me if I did not forget to connect the dongle. Remains to be seen longevity (rechargeable for me) and if it supports the backpack ...
Edit: Please note, lately I've also met some connection problems with Windows 8.1 on Asus ultrabook, but I am not able to correct (sometimes the mouse is still connected and functional, sometimes intermittently hours and it even happens that the connection BT does not reparte without a stop via its mouse interuptor BT). The carrier does not know Logitech confirm that this mouse is fully compatible with Windows 8.1.