My requirements for a mouse were easy, they should have the two additional keys to the left and right on the middle button and be as fit for the hand.
I do not have too big hands (18cm from the middle finger to bale), thus the mouse fits perfectly into the hand, I own them for about 4 months and am very satisfied.
The buttons are using the Logitech software "SetPoint" easily adjustable, actually almost any key is possible, the speeds are super and also the scroll of lines can be changed.
With the software, the mouse only unfolds its full capabilities.
The mouse does not work too high (at the normal price) and is relatively light (about 60g) but you still feel like to move a lot, so it's not "too easy" as it would collapse the same.
For the price strong and a buy recommendation, if you are looking for something simple but functional.
Those looking for more comfort or gamer qualities should look different in any case, because you will find so from 40-50.
