I measured and compared this light with a few Chinese high-lumen budget light here. Even among those higher power lights, it is by far my most favorite. The 519a beam is green at lower power but fabulous at Turbo level, among the “best”/most beautiful of all Nichia beams that I’ve seen.
Output with Samsung 30T was 14000 lumen with just the 519a LEDs, and 15800 lumens with both 519a and SFT40. Among the highest, if not THE hightest, of all Nichia lights, I think.
Summary of outputs with different batteries
“With Samsung 30T 519a: about same as 40T ~14000, SFT40: about same as 40T ~1700. Both LEDs: max 15800 lm”
The reason this light is so unique, a high power light with Nichia LEDs (!), is it was a result of input from BLF posters. There was a thread somewhere for this effort and IIRC, LHD version was out first, then with further input, the 519a was done as the last, and “ultimate” version for hobbyists. I recommend it nearly without reservation for anyone interested in Nichia lights.