First contact with this model rather positive (finishing, handling, driver, packaging ...) and first hours of use ... satisfactory until the evening. Well, look level, waf is not terrible ("What is this ugly printed stripes?!) But at night when the household is calm, G500S shows its ugliest fault: as light as acute wheezing unpleasant sounds as soon as you stop the move (which happens regularly in the Internet consultation). First model returned and replaced immediately by Amazon (Bravo), but the second suffers from the same defect. The configuration of my office is certainly for something: a semi open 1.2 meter wide box that makes "resonance box". After a quick tour of the Internet, this problem is mentioned by many users. It is even recognized by the Digital website which made a box in his test. A reserved for open office or those who do not leave their helmets so. I contacted Logitech which remained in "oh no, not that at home sir, you are surely stumbled on a faulty model", while the Forum notes abound on this subject, a brief little ostrich policy engaging for my future purchases! So, repayment and purchase of Roccat Kone XTD I look forward and I hope silent. Will stay there also to manage waf ("but what is not these lights kéké on your mouse?!") But this is another story.