The midsection and tail-cap grays aren't terribly noticeable but the battery tube is very obvious and is visibly different outside at 2AM under ambient lighting (suburban sky-glow). Even so, I agree there is some overreacting.
I would like to know the price. I may be in.
In that case, if you can see the difference in low light, it's an issue.
Personally the only light where I was bothered a bit with a mismatch was the Eye40vn from Vinh, but in that case it was consistent to everyone, and quite frankly I was floored by the output, so the fact that the tube was a bit darker didn't bother me.
Hopefully for the future the OEM manufacturer learned the lesson here... it's a lot better to spend a bit of extra time on preventing problems then dealing with them after the fact, and enthusiasts are picky people.
I gave my uncle a supbeam m6 as a gift... you know what his complaint was? Too bright :p So no pleasing everyone.
That's awesome, and I completely understand where you're coming from, and how much legwork goes into this kind of stuff. Appreciate the huge effort.
Personally I don't see that it has to be an anonymous BCC'ed PM, I mean the list on page one is visible, and one thing that I like about this place, is for the most part things are very open.
I would say the same about my X40 which arrived about an hour ago. No visible finish discrepancies noted and it is working fine. Looks like they learned from the first group buy! A set of Soshine protected 3400 mAh batteries fit the battery carrier and flashlight tube fine. Do note that this battery carrier only goes in one way.
Please add me to the list please I want 1 
Please PM me the price, I may be in.
I want one now!
Not sure if I should ask this in this post but here it goes anyway. What is the running opinion on which batteries to use for this light. I don’t have 6 of the same cell types. I have only purchased sets of 4 or pairs up until this point and I don’t want to run 4 protected (NCR18650B) with 2 unprotected (NCR18650B) from two separate orders (and batches I would assume) just to have a matching capacity set of 6. So the questions are:
-Would something like the NCR18650B or A work fine (Sammy and Lg 3000/3200mah cells aren’t the best since they are 4.35volt cells and won’t get everything from the built in charging)?
-Would it be better to look into something higher current rated like the NCR18650PF / NCR18650BD / INR18650-29E / US18650NC1
-I don’t see how it would be needed but would this light benefit something like the 25R’s?
-protected or unprotected?
Just looking for suggestions. Thanks in advance! 
The thumbnail says that to deliver 5000 lumens you are going to need about 50 watts or about 8.3 watts per cell. That is going to be about 2.4 amps or so. That is well within the capability of the standard cells like ncr18650A. The PF and BD cells have capability that isn’t needed in this application, and from my experience with the X40, I am not sure protected BD cells will fit. They go into the carrier of the X40, but the carrier doesn’t fit back in the flashlight due to overhang from the protected BD cells. It also raises the same potential issue for protected NCR18650B. I ended up using protected NCR18560A’s in my X40.
The high current capability might buy you a few more lumens for a while, but the lower capacity of IMR/INR cells means significantly shorter run time as well.
Bad Math! 50 divided by three 18650 batteries is 16.6 watts/cell which at 3.7V nominal is about 4.5 amps per battery. Well within the capability of GOOD 18650 batteries but moving into the relatively heavy drain area for standard high capacity batteries optimized for maximum capacity rather than high current delivery. Of course most people will not be using maximum most of the time so average drain will be lower but I was figuring worst case.
Definitely buy a matching set of batteries to run in this light. I mean you'll be fine if you want to fire it up for 3 minutes, with a mismatched set, so long as all are reasonable quality batteries, but you absolutely can't have a mismatched set if you plan to use the light for an extended period of time, or run it for a while on turbo.
Personally I would go for protected PF's, or BD's, but you would also be fine with the ncr18650b. Any gain in turbo for max output from high drains would be fairly negligible.
Protected, because in a multicell light the risks go up, and that protection circuit gives you just that little bit more safety, on top of a good battery chemistry, and the lights own cut off.
I use protected 2600mah Sanyo's mostly because I have a bunch of them, and can swap out even a set of six when I need to. The only lights I do use matched sets on specifically are the FF4, MM15vn, Eye40vn, BTU Shocker Vn, and a 12x plunger, because they only use 4, or 3 batteries each, and put a lot of strain on them.
EDIT: These lights are beasts... you will use the turbo mode, at most 10% of the time if you live anywhere near civilization, or have people nearby. They are not something you turn on max while at a campground... people will complain... :p
If I participate in this GB I’ll be buying a couple sets of new cells too and can’t currently decide between NCR18650BD’s or NCR18650B’s.
I anticipate using turbo extensively because I don’t live anywhere near civilization 
Is the current draw in a stock light significant enough to justify the BD’s or would I be better off with the minor capacity benefit of the 3400’s?
Modded light would make for be an easy cell choice but stock I’m not sure.
Thank you for the replies, very good info. I am leaning towards some PF’’s since they have decent capacity, good max draw at 10amps and the price is right. Hard to justify moving towards BD’s or B’s with the price premium at this time…. but I will doing some more pricing out before coming to a final decision. 
I think if you plan to use turbo a lot, the PFs or BDs are the way to go. Otherwise stick to the 3400 ncrb batteries. Either way I don't think you would have a problem.
Thanks. I think BD’s are the way to go especially if anything ‘changes’ in the light
Why are you dividing by 3? It's a 6 cell light, so ~2-2.5A.
Have the X40, K50, and TN31(made by Supbeam) and all have problems taking long cells with the Chinese protection circuit, the K50 to the point it won’t operate properly. I would buy batteries with the Seiko protection circuit, Keeppower, Xtar, or Mountain Electronics. Sure there are others.
I only own (4) 18650 cells, so I cannot purchase this light thankfully.
Please PM Price.
Quirky, my K50 from the GB works on protected Panasonic 3400s from BG or FT (cant remember which now but definitely one of them). They say nothing of where the IC is made but I would assume China, as they were fairly cheap at the time (maybe 4 or 5 months ago). 2 for under $20 or something like that. Those same cells are a tight fit in a TK61 too.
IIRC, OL mentioned in one of his K50 threads that without protection circuits he would not trust the batteries to stay seated (paraphrasing). Yeah, he fitted unprotected cells and shows a pic with a substantial amount of uncompressed spring, he makes note of the loose fit. About half down the first post of this thread My thoughts on receiving the Supbeam K50 V2