Sounds like this light got problematics >.<
You need semi raised cells. Its touchy its the plastic protector around the tabs its either to raised or to hard and will not flex enough with pressure. But button tops are to big but they will still work fine. My HG2s work fine. You can always bend the ends out on the batteries? You could use magnets fine because the contacts dont spin the tail cap PCB stays still when you loosen and tighten the light but it may not fit still?
Am I reading this correctly? 
Like butcher the cells? Ouch boom
Yep it works they have some slack in them.
The 4S battery configuration version is now listed on the website - http://haikelite.top/index.php/haikelite-mt07-buffalo-cree-xhp70-flashlight-4s.html
The runtimes listed are still the same. Not sure if that's a copy/paste, or they didn't run the tests, or they are really the same.
Same with the MT03 4S. I was told they would be ready next week, so hopefully shipping out next week? I’ve got a pair on order for review.
Did your GA FT cells fit the same as your other FT cells with solder blobs? I’m trying to decide on 30Q FT $30 and adding blobs vs GA FT $36 stock.
Uhh, Yes. Solder blob flats seem to fit the same as SANYO GA's as-is.
Personally I find that I use GA’s more and more now days. Simply because if I do not have a light box nearby I can’t even tell the difference in performance with the naked eyes and the extra runtime is great.
Yea, me too. I mostly use the GA's in the lights I'm using.
4S and 2S2P option. My thoughts are what are you guys doing Haikelite? To whom are you trying to sell the 4S version, and to whom the 2S2P variant? Aren’t you guys going to get bombarded with questions what the difference between the two variants is? Or is this another change that you have implemented when realising that output is reduced with depleting battery charge? Seriously, from a business point of view this doesn’t make sense to me…
I’m finding burrs in the grooves. Threads could be better. With some minor improvements, this could be a great light. Start with a slightly longer battery tube, smoother threads, and either sharper tools or more deburring. You could sand blast more, but I think that will reduce thread quality. Maybe an acid dip?
I don’t care much about 2s or 4s, but that choice is probably going to cause lost sales. 4s is probably the better choice though.
I’d like to see a holster accessory. A kydex holster that puts the light in the head down position is my preference.
I've been using a camera lens bag for it - at least it's protected well.
They intro'd the 4S after the 2S2P, but it's been available since the beginning. I was asked which one I'd prefer.
Why would you chose the 4s over the 2s2p? If they are using a 6v led they will both have almost the same effency?
4S does true buck regulation, 2S2P doesn't. So 4S gives you amp regulation - this is what I was told at least, and I've seen other buck drivers behave like this as well.
I would expect 4S to have flat, constant output instead of slowly trailing off like Tom detailed in his 2S2P review. The trailing off deal might actually be preferable to some as you’ll get longer run times and shouldn’t be able to see the slowly decreasing output unless you measure it.
4S is better in every way, the real question is why someone would chose 2s2p IMO.
If it is a buck driver then 4S gives you constant output without voltage sag issues.
If the LED is 12V then there are less losses and thus more efficient and more light.
Either way, 4S wins.
I chose 2S2P because mostly think'n on upgrading to my own FET based driver. Dunno all the details but I don't mind voltage sag - longer runtimes, no sudden loss of output, no pulling high amps out of almost drained cells. Think all these things were said before...
Also they said protected cells are best with 4S, unprotected best with 2S2P. Hope protected cells can fit in the 4S light...
All those things you listed are in reference to 4S correct? As they would not apply to 2S.
Recommending unprotected cells for the 2s makes sense as it will pull higher amps.
Well let me try to make it clearer. 2S has longer runtimes than 4S because of drooping voltage. 4S will pull more amps, and will try to maintain high amps til the end of the cells -- that's how I understand it.
4S doesn't help much at the turbo level, since it gets too hot in under 10 minutes now in 2S2P, probably less time in 4S.
4S would help in lower modes I would think. It's all these crazy trade-offs goin on. Sure, 4S with constantly held output levels is nice, just can't be done on high amps because of high temps. There probably is a magic level of output that can level an operating temperature. Not sure they can hit that mark though, and probably dependent on other factors of air temperature, air movement, being held in hand, etc.
Dunno, I could be mis-understanding things, but I see pros/cons. If you want a nice stable low and medium mode of operation for the full discharge of the cells, 4S should be better for sure.
I think you are mixing them up backwards. First off there is a big difference if it is a buck or linear driver. I will talk about a buck driver here although the same things apply to a linear driver, just to a much lesser extent.
2s has very little voltage overhead and thus voltage sag will cause output to drop rather quickly. 4S will never drop output till the cells are nearly empty with a buck driver.
Total runtime will be very close between the setups as the total watt hours is held in the cells is the same. The 2S will have a bit more losses to heat due to the amperage but that will be a small issue by comparison.
2S will pull twice the amps for a given output wattage. If the XHP70 is outputting ~50w then it is pretty simple to see this.
7v x 7 amps = 49W of power
14V x 3.5 amps = 49W of power
Higher voltage = less amps
From an eletrical standpoint 4S is the far superior setup in all cases assuming either a buck driver or that you run multiple LED’s in series to make use of the voltage. Higher voltage is simply better.
Thats why electrical lines run hundreds of thousands of volts over the mains and only step it down to 220v at the last minute. Lower voltage is less efficient.