Battery and light questions....

I'm considering getting some rechargable batteries for my 4Sevens Quarks (123x2) and my 4Sevens Maelstrom G5. I was looking around at the different options and noticed that they make the AW 18650 batteries 2200 mah, 2600 mah, and 2900 mah versions. And the AW R17670 in a 1600 mah version (where as the CR123 are 750-950 mah).

Will my Quarks and Maelstrom handle the 1600 mah AW R17670 and the 2900 mah AW 18650? If so what are the benefits/disadvantages using the higher mah rechargeables? Thanks for the help!

Your 2xCR123 will work fine with the 17670 cell, but you may have to peel the the silver label off the AW cell. To use the 18650 cell, you'll need to buy the 18650 body. I have both and prefer the smaller body with a 17670 cell. The 18650 body has too many parts and wants to unscrew in the wrong places. Others may disagree, but that's my preference.

You don't have to worry about mAh that's a electrical charge rating. What you should worry about is voltage - electrical potential energy.

Most flashlights will have a voltage range in which they can safely operate obviously if you go too low the flashlight either won't work or will barely work but if you exceed a certain voltage you have a real potential to damage your electronics.

According to their website the operating range for the Maelstrom G5 is 2.7V - 12V so using 2x16340s fresh off the charger (~8.4V) should be fine.
One 18650 or 17670 fresh off the charger (~4.2V) is fine as well.
If you want a longer runtime go with the 17670 over a 16340 but if you can fit a 18650 then go with that over the other two to maximize runtime.

One issue is that the higher capacity 18650 cells have flat tops that don't play well with all lights -- the positive head won't always make contact with the light without a button. IIRC the Maelstrom won't work with them.

Two things:

1) you want to use an 18650 in the maelstrom to get good run time.

2) you can NOT use flat top cells in the maelstrom - they don't work due to the physical polarity protection mechanism in the light. That means no AW 2600 or 2900 cells. You can use an AW 2200 and have less run time or you can get a button top 18650 from another manufacturer. I have just ordered Redilast 2900mah cells for my lights because they are the same Panasonic cells that AW uses but with a button top. They are well built and highly regarded. Check the threads in the battery forum for more info

I had the newer version of the Maelstrom with the updated UI and it worked perfectly with my AW 2900 cells. I heard that it wouldn't work but figured I'd give it a try anyway and they worked great.

So if I'm understanding this correctly the mah deals w/ runtime. And since I have the newer version Malestrom I can use the 2900mah AW 18650.