They are currently in the process of switching over- from Nichia CS to Nichia DS. They've been using CS for a little while now. I spoke to Todd, the new owner; he sold me 3 Derringers and for a little extra money, upgraded the 3 leds in each of them to DS.
I've always had respect for the eternaLight range and bought an
eternaLight Ergo 3 Red/White (review) when they were on sale - about 3 years ago.
That was well before the Nichia CS and when we were talking about 26000mcd LEDs - some CPF'ers mod'd their eternaLight to use those brighter LEDs.
However although I also covet brighter lights -
one of the main reasons of me getting the eternalight was its
low, low levels.
With newer LEDs that are probably some 3-4X brighter/more efficient means the lowest levels will be 3-4x brighter -
UNLESS eternaLight modify their circuit to give lower levels -
which by the sounds of it they are not - since it is just an LED "upgrade".
For me - I already have lots of brighter LED flashlights -
any of the Cree or Rebels will give so much more light -
I want/need a flashlight that has
LOWER levels .
So modding to brighter LEDs - which most would regard as an "upgrade" -
is actually a downgrade for me
(that's why I never put 26Kmcd LEDs or later Nichia CS LEDs in).
I even got the Red/White option so I could have red LEDs to preserve night (scotopic) vision
and the dim low levels on white so they least disturb any dark adaption I have acquired ......
I even have a single 5mm white LED (2004 vintage) running on a single 2016 for a
Dim LED light........ see
joys of a DIM flashlight.