Illumination characteristics: 1x18650 vs 2xRCR123 vs 2xCR123 ?

Dear Candle Power forum users,

I've been scouring the forums for an answer to the following question but couldn't find one. i'd like to apologize in advance if this question has already been answered in a previous post as i know how people hate repeating themselves. My question is as follows.

Three identical flashlights, the first equipped with a 1x18650 (rechargeable).
the second with 2xRCR123 (rechargeable) and the third with 2xCR123 (disposable).

I know that the rechargeable would probably have a longer running time but
Would there be a difference in output/lumens/brightness/flood/throw? if so, why?

Thank you

Depends on how the driver is optimized.

I have two Sunwayman lights--a V11R and an M11R.

The V11R seems to be optimized to run brighter, much brighter, on a 3.7v li-ion 16340 cell, vs. a primary CR123A.

My M11R runs both of those cells, but it doesn't get appreciably brighter using the 16340 and I was a bit disappointed when it didn't behave as the V11R did.

Some lights, you won't see a difference between 6.0v, 6.4v or 4.2v.

Chris