Badly copied but cheap

Hi,
I've a Logitech MX Revolution used the battery and switch really were worn.
Since I wanted to buy a large mouse again I am initially looked at the cheap.
Result of this mouse:
- Switch the shoulder buttons very soft - pressure point / click comes very late
- Additional key next to the left mouse button is used by Windows Double (redundant) and is not programmable so changeable
- While gambling minor movements will not be read into or about sizes stuttering even on the mouse pad. Sniper Games is not possible.
- Mouse forgets the dpi setting for a computer restart. Must always be reassigned. From time to time, even during operation.

Result:
You can work with it but I went back to my old banzoo mouse.
Those who buy cheap - buy twice.
Orgiginal this mouse is the "Speedlink Decus Core Gaming Mouse" - this comes with software for the corresponding LED and dpi settings.
Prefer to buy the)