The description of the Cyansky Carbon sounds tempting! Constant brightness of 2000 lm for four hours and a modern LiFePO₄ battery, which you hardly ever find in flashlights. Plus practical functions such as the integrated fast-charging via USB-C, a charge level indicator with five separate LEDs and a powerbank function.
All of this joy is somewhat diminished when you look at the rather simple direct-drive driver or the slightly greenish SST-20 LEDs, for which there would have been better alternatives.
And yet the Cyansky Carbon is a good choice in some situations: Even if it is not able to maintain the brightness perfectly, it achieves roughly 2000 lm for around four hours without excessive heat. It is quite suitable as a searchlight for longer missions at distances of around 50 m. It is also currently available for pre-order via Kickstarter at a very attractive price.