1. A very unfortunate shape - with prolonged use, the brush gets very tired. The main reason is the shape tapering to the top in places that you hold with your fingers when moving the mouse. After three months of use, I began to think about buying another mouse. Since the brush of the right hand is already really starting to hurt. I am even afraid of the already remote consequences for the health of the hand, if you continue to use it. 2. Too sensitive scroll wheel, at the slightest touch they scroll. When viewing a page in a browser, this is not important, but if you watch a video in Telegram and keep your hand on the mouse, then there is a good chance that there will be a transition to the next media file right in the middle of viewing. 3. Crooked software in terms of saving settings - they are not saved! I do not need a backlight on it and it can be easily turned off in the program, but if the settings program is closed, the mouse starts to glow. The save settings button is there then for what? I really regretted the purchase. I do not recommend!