UPDATE mixed reception: Great light, moderate holder!

Overall, I am satisfied with the Sigma LIGHTster:
The brightness of the lamp is an opportunity for cyclists more than adequate, in my case, it is the most brightest bicycle lamp that I've ever had on a bike. And thanks to the two-stage battery indicator (an LED lights up when the battery depletion first green, and later red) is to be informed. Rainwater sealing the lamp is also, as I try "had". For advantageous I also consider the possibility to open the battery compartment by means of a button press. The button is quite stiff, accidental opening, making it virtually impossible. The opening by pressing a button, I think this is a far better solution than the partially secured with screws battery compartments of other lamps.

The only drawback is unfortunately the lamp holder: They can screw it to the bicycle, the lamp is then pushed onto a bar until it clicks. Since you can not screw it to the bicycle, the lamp, you have to clip them by repeatedly plugging and unplugging, if you do not want to risk a theft of the lamp. Judging my experience with other lamps after However, such clip fuses unfortunately very susceptible to breakage. I hope that this clip backup lasts longer. And if the "break" is that you can reorder the thus become unusable mount Sigma ...

UPDATE:
Now the spotlight I went to the ground and the first time! I had not clicked it correctly. Of course, that was my own fault and is not to chalk the product. At slow bike ride on road asphalt pitched, but it did not break, and the lamp is working happily without problem. Another plus!

Positives:
- High brightness / luminous width
- Lamp is robust and at least splashproof
- Easy battery replacement

Negatives:
- Lamp holder and light fixture is prone to breakage by clip fixing in the long run