Positives:
Very light
Very accurate
Very good skate teflons.
Control screen below which allows to change these parameters without going through the driver
Neutral points:
Ambidextrous shape
Wired
4-way button not scroll
customization (colors ...)
Metal Surface worse than baby skin but does not slide, however.
Negative points:
buttons on the right can not be used by a right-handed
No mac driver now but should be out soon
A very good mouse a bit expensive however