Old flashaholic! Someone give me a rundown on the new flashlight technology and must haves!

The battery thread is here: https://budgetlightforum.com/t/-/2647

The 3100mAh batteries can be had in both protected and unprotected. I believe your light must not have a voltage cutoff greater than 2.5 volts to utilize the full potential of these cells.

I paid over 20USD with shipping for my AW2900. Yes, they are expensive but at the time it was about the best battery I could get. Now that I have the CK batteries at nearly half the price for a newer Panasonic cell, I will pick up a couple of those for my EDC.