The lamp is good .......

and illuminates the road at a distance up to 15 meters good. (but comes in brightness and lighting range by no means at the approach of a motorcycle).
Here an illuminated rectangle on the road with a size of about 5m by 5m is formed. (As I said is the "most distant side of the rectangle of light in 15 meters distance from the lamp).
This said rectangular one can speak of a serh good illumination (For cycling conditions).
The solution to the charging cable is user-friendly.
About the lighting time, especially in winter, I dare not have any information.

However, deductions there for the very simple (and wakelig schwingungsfödernd) designed attachment that can never keep up with the good lamp.

Since the bracket is bolted nich but merely clamped, and is designed to be very thin, uneven road surfaces are increasingly passed on to the lamp, which manifests itself in a corresponding thereto trembling of the light cone.
In addition, the lamp, and thus the light cone slips while driving down, since the clamping action of the clamp arm is not sufficient in combination with the rubber pad for the weight of the lamp and one must correct often after.
Clearly at such a lamp includes stable screw fastening, which allows only small vibrations.

The lamp itself is good.

Therefore, for me only 4 stars.