Even if you set aside the stupid charging situation, it's still a bad mouse. The multitouch capabilities are not well used by the software, and it's the only mouse I've ever used that routinely sends scroll events while I'm just trying to click or drag. Their laptops are pretty good at rejecting accidental touchpad inputs despite those touchpads being quite large, but the mouse is a constant source of unintentional inputs.

This! It is a bad design because it is a compromise. It is flat because of the need of multitouch, which doesn't get used. And because of this flatness it is not ergonomic to hold it.

It is neither a good trackpad replacement nor a good mouse design.