I use in the private sector for nine years the TackMan Marble FX Logitech and am completely happy and satisfied. The logical consequence was that I've worried a half years in office the "successor" after the mouse despite intenisven use of keyboard shortcuts but started my shoulder to cause problems. Unfortunately, the current TrackMan is by far not as ergonomic as his great-grandfather: The left mouse button sits even for my smallish hands too far forward (towards the wrist) and is too tight. Also do not push it down but more inwards towards the palm one. I have to bend the thumb in order to operate with the necessary force. The result is that I now after long working days, although no longer the shoulder, but the thumb tendon hurts. Since I am the evening happy if I can re at home comfortably click with extended thumbs "down" instead of angled thumb "inside". Even the ball is significantly smaller and puts more deeply in the housing of TrackMan, so that one has a smaller radius of the movement. On a 24 "widescreen display you already come since the cranks. This can my ancient copy even better. Apart from this ergonomic dilemma of Trackman is however well equipped: it has a scroll wheel and a variety of extra buttons (which I never use, however, and therefore can describe at this point gar nich detail). The functionality is fine, I have no dropouts. However, the battery life is quite limited, for two to three months they must be replaced (I use Eneloops). As I said, that are data from the hardcore use. In the private sector they keep you safe longer. For at home I will probably look at the trackball from Kensington, for my old baby has not got a new Logitech driver for Vista or Windows 7 on.
