The mouse itself has not intense after 10 months use the usual Logitech Quality & has no shortcomings.
I am most of the "endless scroll wheel" excited about what the search of very large folders and the scrolling through long websites much easier, the settings for the wheel you can adjust and by detecting even very accurate actions are possible.
The mouse fits comfortably in your hand is not too shallow & ergonomic in use.
The normal keys left as the right to work is also very good and I was able to notice any mistakes now & then to the very good for me, the side buttons for right links are arranged & to facilitate operation of Win8.
I very often use the downshift function but very rarely the Vorschaltenfunktion & so I left the upper rear button in the preset switching back function.
The upper front button I have with the program switch function (item 3 in the Logitech key assignment) is & can so by pressing the selfsame through all apps already in use, the desktop, or by switching to the home page without having to into the top left corner.
The bottom thumb button I with the start screen (dot 8 in the Logitech key assignment) is & can at any time turn immediately to the home page without having to the bottom left corner.
These functions can be set with all 3 extra keys mice from Logitech on all keys in all versions, however, as it works with modifier keys from other vendors, I can not, however, specify I think there are also as opportunities.
In conjunction with the mouse Win8 for me is extremely valuable, they do not want to miss and hope that some messages here are not also apply to my copy.
I hope a few Win8-users with the instructions to be able to help on the key assignment bit & wish a lot of fun.