Just purchased a brand new noname XM-L focusable flashlight...

I’ve only run it with two 18650 cells. Never tried any other cell configuration. I’ve had it running continuously on full blast for about an hour, it performed well but I do not have the experience as many others here have, so I cant help much. I haven’t tested what current it pulls on the tail cap.

It did however have the dreaded next mode feature, but I solved that with the help of this thread, post #33 to be exact: Attention! Solution for most of those next mode memory drivers!
Post #72 I posted a photo of the driver, followed by comments on the solution.