I'm not sure where you got the amp ratings but the Lume1 driver in the E12R is regulated to 6A and has FET for turbo. The E12C has a FET+12 driver with a max regulated level of 4.2A but it is much less efficient compared to the buck driver.

Another advantage for the E12R is the optic. It's a much better optic with a nice round throwy hotspot.

I actually own both of these lights and am currently trying to sell my E12C lol

Edit: I see now that you're talking about the power bank amp ratings 🤦‍♂️

I have both, E12r all the way due mostly to the better driver and optic. Plus I also like how it's visually smaller due to the way the button area is flat rather than angled. (Some speak highly of the angled button's ergonomics though so ymmv.) Another thing is the smooth ramping on my E12c isn't very smooth at all.