Review on Perixx PERIPRO-303 X4A Trackball With 1.34-Inch Replacement Ball For Perimice And M570 - 4-In-1 Multi-Color Trackball In Red, Purple, Pink, And Lavender With Stylish Storage Box by Scott Mcgowan

Bought for my M570, and it works great. Previously, if you wanted a red ball in your M570, then you would have to jump through some hoops and end up with a story like this:There is a community of M570 enthusiasts out there, and many claim that replacing the M570's ball (grey-blue mouse, blue ball) with the Logitech Cordless TrackMan Wheel's ball (same form factor as M570, butlight grey-ish mouse, red ball) improves performance of the M570. Good luck finding the Logitech Cordless TrackMan Wheel by the way. I did find one, and I did the swap, and all it did was slow my pointer speed down considerably. In fact, I had to crank the pointer speed up all the way in Windows just to get back to middle-ground pointer speed. Why does it do this? I don't know. Ball material, the quantity or arrangement of the small dots on the ball - I can't say for sure.Enter this Perixx trackball. This will restore your M570 to the same pointer speed that the original blue trackball offered. Score!