Mine finally got movement - 12 days from LAX to NJ, get'n closer...
Did you keep your white one as it was? I know you had ordered a green one and it came as white, but I thought you were getting a green led sent to you. At the higher power levels the green gets more yellowish green than green. In pictures it shows as more green than to the eye. If you ever seen any of the Phillips Hue lights it would be like gen2 green and not like gen3. But the increase in throw is noticeable more than the w1. I actually use the green on more than the white for spotting deer at long distances on the property.
Yea, I did get the green LED - still sit'n on the table as a reminder :FACEPALM: . The white is still in the K1 but specially now that I have the 90.2 coming, I gotta swap in the green, then can re-use the white in another light, perhaps my old BOSS1. Too many mods to do, not enough time. I thought the green could take more amps though? Hank says they use the same driver, therefore must be the same max amps?? So maybe the green LED could even be pushed further, though it's tint shift may be worse?
Mine is here. First impression well I think I ordered it in brown, this says grey. I don’t care just ordered it to be different than the others. Loaded it up with a new Molicel P42A. It looks a lot like what I expect from a sbt90 reflector light. This is my first .2 version but I’m very used to the small sun from other sst, sbt lights that I have. In my basement it’s very bright, lots of intensity and lots of spill. Very different than the w1. I’m really surprised that it’s not the instant heat that I was really expecting. Nothing wrong with that but it tells me that this led could be pushed a lot harder, although for mostly more heat I guess. Will be nice to see what everybody else thinks. I can already tell it’s going to be a nice do everything light.
Did you compared with FTO3S? Image would probably helping A LOT…Thanks!
I ordered a ft03S but they cancelled the order.
Here is the sbt90.2, green w1, and white w1.
Not good aim, but all 3 will reach the furthest trees. The w1s will both do it with much more of a concentrated hotspot vs the sbt 90.2 that is much more diffuse.
Lambda Varapower 4D SBT70
Noctigon K1 SBT90.2
I received my K1 with 90.2 today. The 90.2 might look diffuse next to the W1, but next to anything else I own the 90.2 is great. I pointed it down the street tonight and some people a block away got lit up; they had some choice words about the effing light. 
Pointing it across the open field at distant trees that my previous best throwers (DEFT, TK70) just barely show a ghost of a shape, the K1 fully illuminated them with good detail.
Of the ones I have it’s by far the most useful. W1 have very minor bump when switching to Turbo but not the 90.2. It’s Turbo is massively brighter.
Has anyone had the chance to see if the battery tube will fit onto a D4S?
They seem to be the same size
The K1’s battery tube (21700) does not fit the D4S (26650). It is not wide enough.
Ah. Would it be possible to make a custom order production run of battery tubes and tailcaps, essentially K1 tubes but without the charger and different thread diameter at the head, for 21700 batteries that will fit the D4S/D4SV2?
Apologies that my first post is a question, but I’m stuck between some things with not enough knowledge and experience to choose one way or another.
I’d like to order a Noctigon K1 but as a floody thrower… if that makes any sense lol… basically, while I need some good distance, I’ll also need some peripheral illumination as well. The problem comes with the heat: I want it to run on high output levels for long periods of time without thermal issues. Lower battery drain is a plus as well.
I’ve narrowed it down to the XHP35 and the SBT90.2. Both produce more than enough throw, but are they going to step down in a few minutes (seconds?) due to excessive heat? I’ve tried to read up on voltage and current and all that jazz, but I’ll be the first to admit I’m a neophyte with regards to interpreting these _
This will be for open outdoor use, hence the focus on low heat/high endurance and throw vs flood
I’ve some experience with higher power flashlights (I own a D4v1 219C, a KR4 XP-L HI 6000, and a KR4 mule XPL-HI 5000 [my favorite and the daily carry; also a firestarter])
Again, long time lurker, first time poster, sorry to start with a question, but Hi Everybody!™ 
Welcome to BLF!
The XHP35 won’t disappoint you
Not answering your question directly but a thing to take into account:
Do you need wide or bright side illumination? Or both?
I ask because reflector depth has a big impact on the side illumination (which we call spill).
A deep one will produce narrow spill that won’t hit many things around you. Therefore it will disturb your vision less.
A shallow will produce wide spill that is very useful f.e. while walking.
Note that spill brightness is not affected by reflector but purely by LED output. The brighter the better.
Y’all are awesome and that was fast!
I was thinking the XHP35 would be best, but its a 12V (isn’t it?) so I was worried being a different voltage it might require less efficient drivers and thus would produce more heat? Perhaps my logic is off, but that’s why I figured I’d defer to y’alls superior knowledge 
As for the width to brightness of the spill, ideally I’d want both, but I think it would be best to shoot for wide for peripheral vision and situational awareness; I don’t need to see the critter in detail, just know he’s there and off to the side. Does that make sense? lol
Multi-cell light like that deserves the 90.2 more than the K1!
Agree there - I got in another couple SBT90.2's, now just need time.
An xhp35 is a 12v led, so off a 1 cell light it needs a boost driver to work (step up 4.2v to 12v). Simon sells a really good boost driver on Aliexpress Xhp35 Driver US $9.65 | XHP35 HI driver, run on single lithium battery 3.0-4.2V, output current max 2.3A, 4 modes 淘宝网 - 淘！我喜欢 but it’s 22mm diameter so take that into account as it may or may not fit the KR1. I think you’d be good with an sst40 or maybe ab xhp50.2 3v led. The 50.2 gives good spill and decent throw. The sst40 throws more and also gives good spill. They both run off a single lithium ion.
I’m not sure, I don’t have K1 but looking at the picture I think it has a somewhat narrow spill. It may not be the best host after all…
This reminds me of an old thread but I’m not sure if it’s still relevant.
Increasing voltage is always at least fairly efficient and sometimes very efficient. Decreasing can vary from very efficient to inefficient.
In the case of K1 the XHP35 driver will be more efficient.
But driver efficiency is not as important as LED efficiency.
I’m not sure but I believe that at the same spill brightness (or lumens - these are directly proportional to spill brightness) SBT90.2 will be more efficient, consuming less electricity.
At the same spot brightness, XHP35 HI will consume less electricity. But I’m not sure if it will be more or less efficient (because efficiency is basically light-output divided by power consumption. SBT90.2 will consume more power but it will also output more light).
If someone wants both flood and throw, one easy option is to put some DC-Fix over the lens of a thrower. Perhaps even just part of the lens. That will reduce throw and convert it to a very wide flood area… and you can adjust the balance between the two by changing how much of the lens is covered. One good compromise is to put a circle of the stuff right in the middle of the lens, because that will provide good short-range flood without affecting the throw distance very much. The throw part of the beam mostly shines through the outer edges.