EDIT: Left button is no longer held after less than 6 months. Give this mouse a big chance. Overall, this is a great Logitech g502 series wireless clone for a pretty good price. The sensor and accuracy are good, the weight and ergonomics are not exactly like the g502 but very close. The big problem though is that this is supposed to be a gaming mouse, but it does have a slight "wake up" delay even if you don't move it for 10-20 seconds. By the time it took me to type that first paragraph, he had already fallen into a light sleep, and there was a slight waking delay when I moved the mouse to make changes. For normal use it doesn't matter much, but for games it can mean virtual life or death! Imagine you are an FPS sniper. You sit with a purpose and wait for someone to turn the corner. They are there! Only now do you go about fine-tuning your aiming and shooting, only to have a wake-up delay and miss your target. There is a sleep timeout setting in the Razer software, but that doesn't appear to be the case. Work. I set it to 15 minutes, which is the maximum, but the mouse still has a slight lag when it hasn't been moved for a short time. Note. It's in USB dongle mode, I haven't tried it in Bluetooth settings.