Great mouse all around, extremely high quality hardware (the sensor is amazing!!!), only issue is that it is extremely easy to accidentally right click on it. Had never had this issue on any other mouse and it is fairly annoying at times.
If the heart beat sensor isn't your thing you can just turn it off in the software and that will turn off the little green light as well.
If the heart beat sensor isn't your thing you can just turn it off in the software and that will turn off the little green light as well.