The thing has a certain volume, but not tiring, especially because of the thumbhole, which easily reached the two buttons "Forward / Reverse", handy in a browser, for example. The wheel with detents or free is a find, and additional function for side scrolling is a real pleasure. She also makes a click, which is added to the left and right, and everything is customizable. I love it. By cons, his little sister Logitech LS1, also very nice although less complete, quickly showed signs of fatigue, and became unusable in less than a month. Fingers crossed for this one.
