Meteor driver was an open-source project:
http://forum.fonarevka.ru/showthread.php?t=17352
The only closed thing is software, opened one is little different.
There is no problem in making some of them, but I live in city and country where it is hard to get most of components.
MT-G2 at 8Amps: 7V drop, 56W, 3570Lm, less than 64 Lm/W. Is that your target?
Ok, lets imagine that I have trusted that you really need 3600 lumens. Quad 219C can give them:
4x3A, 3.25V drop, 39W, 3600 lumens, 92 Lm/W. (parallel)
3A, 4x3.25V drop, 39W, 3600 lumens, 92 Lm/W. (serial)
This example is good because low voltage drop gives us possibility using this mode with low voltage single cell.
Parallel connection with buck driver (90% eff.) - 13.3Amp from single cell.
Serial connection with boost driver (85% eff.) - 14.1Amp from single cell.
Is this current to big for IMR26650? I don`t think so.
Is each cell in 2x26650 config discharging with 7Amp will have 30% more capacity than one discharging with 14Amp? If you are using ultrafire cells, may be. Basen 26650 4500mAh will have almost no difference.
It is funny to hear about internal cell resistance problems, 5-8 years ago it was normal to have power tool with 20Amp motor and 13R cells inside, and even this config could work for a long time and be in good condition after hundreds of fast charge-discharge cycles.
Now we have much better cells, with much higher capacity, much lower internal resistance, much higher listed discharge rate, and we are talking about bigger 26650 size cells, is it good to dischage it with 15Amp or not. Yes this is not good, you will have about 5% less capacity than rated, but it doesn`t matter if lots of members use linear drivers, improper optics, close its outer edge or even cut them down, leds in 3x rated power and etc. what gives much more lumens lost.
Using boost driver in single 18* cell flashlight is bad idea cause you will have 10W driver for $30+.
Using boost driver in 26650 host is more possible, I think pills can be changed to those which can accept 25mm driver.