Reserved !
I still have to add a thing or two 
8/5 - Updated beamshots
Nice review George.
It is interesting how much is the battery current and voltage after 20 minutes on high mode?
Thanks for the review. The XHP50.2 in combination with the H1A boost driver is impressively efficient. The same combination and results that djozz found in the KDIY KF8.
The throw suffers though, from a combination of the low current density and new cree flip chip design LEDs, which inherently have less luminance and throw.
Thanks for the review. I want this light or at least the driver. Its crazy that 2k lumen single cell c8s are a ordinary thing now. With this set up or 3v its over 2k and with the XP-L2 it’s over 2k as well. I think this driver with a mtg2 would work nice in a c8 with a single cell.
Great review
Thank you for the review.
Enjoy 
2000 lumen highest with just only 4.7A, doubt it :exclamation:
Why? The battery voltage under load should be about 3.8V, using a good battery, so this means about 3.8 V *4.7 A = 17.86 W input into driver, with the 90% efficiency of the H1A this means 0.9*17.86 W=16.074 W to the led, and cree lists 2654 lumen with the 18W max input, taking this into account, and 10% losses from reflector/lens, expected lumens are 2654 lm/18 W*16.074 W*0.9 = 2133.02 lm, so above the 2000 lm at startup.
(Correct me if my math is wrong)
Maybe you are right, im just amazed how far led technology has gone
The efficiency of LED now is really impressive
Btw
According to this test
The led gives 2200 lumen at 18w
And your math said the led recieve 16W, so i guess the lumen is about 2000-2100 lumen
With 10% loss of glass and reflector, maybe the number is nearly below 2000 lumen
Still impressive
Thanks for your kind words and nice comments explaining some great things . I was away from home for a few days , so now i got the time to read the comments and update the review
Beamshots coming in a few minutes , and conclusion maybe too .
Great review. Got one of these myself and am pleasantly impressed. Feels like a comfortable 2000 lumens to the naked eye compared to convoy c8 and L6, and slots nicely in between in terms of performance.
Reckon you can convince kaidomain to put a xhp35 hi into the same set up? Even keeping the current around the 4A level? I’d buy that. Don’t have enough time or skills for even simple mods myself.
xhp35 is a 12V led , compared to the xhp50.2 that runs at 6V , so it will be a little more complicated …
An xhp35 running at 2 amps would be awesome in a C8 , but heat wouldn’t be so great…
Huh! I assumed because the xhp 50 and 70 came in 6V and 12V the 35 would also. Oh well, thanks for pointing that out.
On another note, I get a brief bright flicker whenever I enter low mode on mine. Just mine or do other units also do this?
It is a common thing in many lights when going from highest to lowest level, it is hardware-related but can be suppressed by the software. (I’m not an expert).
+1 for me to
Yes , mine does that too . I guess Jos gave a reasonable explanation 
Out of interest, with the H1A driver that is being used, is there an MCU on-board? I've looked at the photos, and everything seems to be obscured by a huge (I assume) inductor?
been thinking of getting a couple, wonder if they would slide some batteries in them for shipping purposes.
thanks for reviewing the light.
You could ask them , they will probably be able to do that.