I find them very good

I ordered the headlamp, because I need it in the dark season for jogging. My running time is approximately one hour.
The processing of the headlamp is impeccable. The lamp body is made of aluminum. The threads are clean and greased processed. It hooked and caught nothing when opening and closing the battery compartment. My 18650 PCB, Button Top Panasonic battery with 3,400 mAh fits in exactly.
What I also liked the fact that the battery is in the lamp body. This no cable's in the way.
An instruction manual is in German here. It says that after 3 minutes the lamp from the Turbo mode downshifts and is temperature controlled and regulated at 50 degrees down.
For me that was equal to the occasion to test the lamp. As it was dark I went out on the track. That evening we had 0.5 degrees Celsius in light fog.
The illumination angle of 100 degrees is really great. One can see the end of the light cone (left / right) only when you turn your eyes all the way out. Similarly the edges of a pair of spectacles. I have the lamp set to focus about 15 feet in front of me. In this area the night becomes day and the focus is clearly visible on the floor.
I think the lighting range is specified with 85 meters. I think that's a little optimistic. The light may perhaps arrive there, but illuminating nothing. The maximum range is really not well lit, is about 40 to 45 meters. In my mind that's running perfectly adequate. For brisk cycling in the field, I would not take them now necessarily.
While running I have repeatedly touched the lamp body. And my hand was much warmer than the bulb. And she has not regulated during the walk down!
The gradation of the individual lighting levels I find very good. For everyday running I'm not likely to use the lamp in turbo mode, but go down a notch or two.
Conclusion: A very successful lamp, with a great price / performance ratio. For my purposes, I would buy me back and can fully recommend.

I hope the little report could help you a bit further.