First thing I have to say is that this is by far the best mouse I've ever used. The tracking and battery life of this thing is phenomenal. It's just as good as wired mice and as far as I can see, there's no detectable latency.
Now why the 2 stars?
Because this mouse has a problem with double clicking, where one mouse click triggers multiple mouse clicks.
My first Pro Wireless lasted just over a week before it started double clicking when the left mouse button is held down and pressure is slowly released. I'm pretty sure it had been happening before that because I've noticed myself sometimes clicking on things I didn't want to.
Amazon was kind enough to immediately send a replacement and the replacement started to double click after just 3 days.
That's why despite the Pro Wireless being by far the best mouse I've ever used, I'm giving it 2 stars and I cannot recommend this mouse to anyone unless they want to gamble with returns and hope they get one that doesn't double click.
If Logitech ever reads this, know that again, this is by far the best mouse I've ever used, and if you would acknowledge and fix the issue in either a re-design/next model, I would buy it in a heartbeat.