This mouse is a very good model, it is undeniable! However for the price it costs, I find deplorable quality. I personally had to send for service after only 6 months of use because the sensor began to fail. The service is pretty good, I received a new one in a few days (one week can be given that the service is in Denmark). Since then, more problem at the sensor, however, the gray layer seffrite very quickly and "holes" are now visible. The white layer of plastic we see mounting holes is not very aesthetic ... in short a mouse with an excellent sensor and undeniable qualities (integrated processor, management / personalization of profiles very driven, quality of the sensor, ...) However, the quality of materials and the reliability of the sensor is to review ... I honestly do not recommend this model even though it has been over 1 year since I use it and I am generally satisfied. I think just at this price you can get better and more reliable.