Samsung 30Q's are good, a lot of BLF community use, I don't have any 18350 lights, but I got these awhile back for FW3A light: https://www.illumn.com/batteries-chargers-and-powerpax-carriers/18650-samsung-3000mah-inr18650-30q-high-discharge-flat-top.htmlThese are flat tops, the have button tops too. If you are getting a light that requires high drain cells may need to stick with unprotected, but I'm not 100% sure, I think a lot of these lights may trip protection circuit on turbo. Check manufacturers specs for max battery length light can handle and if you can/need to use prot/unprotected
LG INR 18650 HG2 3000 mA - 20ASamsung INR 18650 30Q 3000 mA (15 A)Sony Murata VTC6 3000 mA (30A)If you think 10 A is enough, look also Sanyo NCR 18650 GA 3350 mA (10A) or LG INR 18650 MH1 3200mA (10A)if you are looking for protected batteries I have had good experiences with KeepPower, it produces 10 A and 15 A protected batteriesI buy batteries from a Dutch seller but I know it also fast ships to the USA
What flashlights are you planning on using these batteries?