After 2 years it still works well, very precise and ergonomic, the plastic does not stick to your fingers after a few years as some known brand but yet very good (its starts with M and ends with a T ;-)) which is programmed for me to lobsolescence ... ratchet free wheel or the push of a button very accessible. (Keeps its inertia until 25 sec after 2 years !!!) quickly adjustable sensitivity on touch. Battery level indicator (well, it uses a lot) with battery and provides cable (mouse son can become) for USB charging.