You can find the full review on my website in english and german.

It's also available on BLF and german TLF.

Summary

The light left quite an impression on me. I didn’t expect the advertising promises to come so close to reality. Well, it’s not 1,500 lumens constant for 2.5 hours, and without the fan, the light would be a pretty normal, large right-angle light.

The UI is fine, the button is pleasant to operate. The clip seems well thought out, the headband works, but an upgrade wouldn’t be bad. So the basics are met.
Pair that with the active cooling, the good runtime, and the high sustained output, and it quickly becomes clear that Sofirn is offering quite a lot of light for the price.

As with any light with active cooling and thus moving parts, time must show whether the whole thing also withstands dust and moisture. With the IP6 rating and my impression of the light, I am in good spirits that the light is designed to be sufficiently robust.
Nevertheless, call me a coward, but I would not wash the light under running water as stated in the instruction manual.

Anyone who likes high output, enjoys playing with technical innovations, or simply needs a versatile right-angle light should definitely take a look at the HS45. I’m having a lot of fun with mine!

Please read the "potential Problems" section in the Review before buying!