I use the trackman marble and like it. In Firefox, clicking one of the side buttons and initiates the main trackball to act as a scroller. Nice, but I haven't s

I use the trackman marble and like it. In Firefox, clicking one of the side buttons and initiates the main trackball to act as a scroller. Nice, but I haven't seen this in other applications so scrolling becomes cumbersome. I find many innovative, significantly redesigned keyboards lacking data to support that they provide health advantages relative to the increased price. I thus stick to the Microsoft ergonomic keyboard line. I am using the Microsoft Natural Ergonomic 4000 but find the key action stiff. I will probably want to check out the 'Elite' version.