In terms of quality, it's just a great mouse. Low bow for abandoning the built-in battery in favor of batteries - you can use your own batteries. With intensive use ~ 12 hours a day in HI mode over the air, two IKEA 2450 batteries last for 2-3 months. The main disappointment: a year later, LMB began to give a double click. Luckily, it has a 3 year warranty. Before that, I used the G602 Proteus and a similar problem - a year later the side (!) Keys died. Both devices use omron buttons. Despite what happened, I recommend the mouse.