Ok, let me be "that guy" for a change...
I'll be honest. I think it is a very bad light for night riding, and in that sense it doesn't impress me at all. It's ridiculous, yes, but not something I would boast in front of actual cyclists.
It is way too excessive, if not outright dangerous for real-world use (and even more so the HID array from the other video). I consider it to be a product of mindless number race that ultimately makes no sense: by effect alone, what I've seen in the video feels more like 4000 lm. To be honest, even that seems excessive, because typical car headlights are only 2000 to 3000 lm each, and cars need those only because they run much faster. How is it that a slow moving bike might suddenly need 7+ times more light? Read on for our analysis!™
Construction
...Would fit a motorbike much better. As it is, the whole array is too heavy. A typical complete bike assembly with an aluminum frame weighs 10–13 kg, this lamp alone adds about 4 kg to that number. For the record, that's more than a pack of 15 Lupine Bettys glued together. Moreover, the assembly is too large and complicated. You need to pack your belongings (emergency kits, water flask, etc.) in a backpack instead of places now occupied with parts of the assembly, putting extra strain on yourself in addition to carrying forward those extra four kilograms. Your heavy panting at the end of the first video is very convincing! If covering some 350 m leaves you out of breath like that, you should look into reducing and optimizing your load instead of doing exactly the opposite.
Also, there are too many weak points scattered around the frame. With lamp in the front, makeshift cooler in the middle and power supply in the back you're just asking for trouble in night riding—a potentially dangerous enterprise that needs safety and robustness above all.
Usage safety
First of all, it runs too hot. It would expand the list of possible accident injuries far better than shrink it by the virtue of letting you see things better. And the injuries can't be ruled out because with an assembly so fragile and complicated, there are too many things that can go wrong with this light. Would it even be safe to use if a heavy rain catches you on the way home?
Another point to consider is that the beam is too wide for its purpose, yet too bright at the same time. You're bathed in glare from things you don't even need to see when you're on a bike. In the video, even dark grey trees roll over into white; any actual white or reflective (wet or shiny) surfaces could easily distract you or disrupt your vision, causing accidents. You can't use this light where you might meet other people even theoretically, either, because being hit in the face by 40000 lm at night would be pretty annoying, and might induce seizures in photosensitive people.
Illumination efficiency
This design might be power-efficient for the amount of power it draws, but the fact is that it needs too much power to achieve a much simpler purpose. It's essentially a low (close sight) beam overpowered to reach the intensity of a high (far sight) beam, completely ignoring all the good reasons for the distinction. It heaps more of the same 26° beam originating from the same spot for every distinct illumination task, not unlike using a single screwdriver for various screw heads.
The fact that the light uses some of the poorest contemporary high-power LEDs when it comes to color rendition doesn't help: XM-L U2 are only available in cool white, spec'd at ~65 CRI; whereas just lowering the CCT to about 4500 K would bump the color rendition up to ~75 CRI and give you more natural greens and browns. You have more than enough surplus lumens to spare for that purpose...
Bottom line: I understand that most of the decisions were dictated by cheapness and convenience, but a cleverly done combination of a softly diffused high-CRI low beam and a concentrated high beam could achieve exactly the same purpose in at most 40 W while having virtually none of the disadvantages outlined above, but of course some 3000-something lumen isn't exactly as mind-boggling as 40000—for both good and bad reasons.
