Need help on battery choices

Hi

I’m new here and have been using this forum as a reference to choose my first flashlight and only last week did I decided to create an account. I saw C8s as heavily recommended and since the L4 is so similar I decided to buy the L4. I currently have the L4 on the way from FastTech. My purchase was on the 1st of March got separated into 2 shipments, one has it status as “Order Received” and the other as “Pending Payment”. Any idea why? I also got myself an Acebeam K40M from Banggood’s flashdeal earlier today and i would like to have your opinions on recommended batteries for these lights for the longest runtime and highest light output. Maybe a few suggestion on light and simple mods for them? I tried dedoming an led and I think I destroyed it because that zoomie don’t work no more but my other Aleto twisty did. Responses will greatly be appreciated!! 0:) 0:)

Regards
Wrath