I modded 4000K 90 CRI XP-L2 leds in my black D4 today. Starts at 4300 (djozz-)lumen with 3800 lumen at 16 seconds, then thermoregulation kicked in.
This was a U6 bin, a V6 bin should be 5400 lumen at start-up.
Not so happy with the tint.
More info in WDYMT