The lumen output of the more powerful lights have no standard I do believe. IOW,what a 1000L means to one company it does not mean to another company. I also do not believe that there is any industry standard or enforcement in regards to stated output.
I find that some of the adjustable output(hi/med/low/strobe/SOS)lights are simply a PITA. Especially the ones that I use for non-hunting purposes. My hunting/backpack lights all do have a adjustable output feature. There are some instances that I really do not need the light to put out full power. However all my hunting lights are of the >2000L variety.
I have a firm belief that when you need light to find something,you need the brightest light that is reasonably portable. To light up a trail,to find the smallest evidence of blood,broken weeds,or an animal track,you need light. The brightest and whitest possible.
As of now,the only device that I own that uses the CR123 type batts is my thermal. It uses three,and will last for an "honest" 6.5 hours even when I use the "refresh" feature fairly often. --- pruhdlr