Wheel squeak, the annoying, especially in a quiet working environment. Otherwise, a great mouse, you use for Office, Adobe, 3D Max and Autocad. Cover the Bateriefachs is not valent, and detracts from the ansich good overall impression. The Bateriefach can not easily close. You need a bit of flair, and the battery contact is not right there, a little fiddly special which is due to the quality of the closure / cap.
The squeaking simply should not be in the price range!