I gave up on CR123 batteries sometime back due to there low mAh ratting of 1500. I tried the RCR123 batteries but their mAh ratting was 500-800 mAh, with most models having capacity around 700-750. Compare that to my 21700 Lithium-ion 5000 mAh capacity and you can see why I upgraded.  The CR123 batteries are not built for high discharge devises like my flashlights.

Two CR123 batteries are about 5/16" shorter than a single 21700 and smaller in diameter but the performance is so much better with the 21700. I bought my Warrior flashlight in 2019 and it is still going strong with the original battery. A bit over a year old.

I also have a Coast HP17 adjustable flashlight that takes 3 D Cells.  It is primarily a police flashlight and I like it.  I keep it in the boat but it seems like the batteries are low when I want to use it.  If I ever loose it, or it gets beat up, I will replace it with another Olight Seeker 2.  The Coast HP17 is the only standard battery flashlight I have now.

The one feature of the Olight flashlights I really like is their magnetic battering charging system.  Especially with the L bracket mount.  I always know where my flashlights are located and that they are fully charged every time I pick one up.

Another thing that I like is the high output of my lights.  If I have an intruder at night, a blinding light in the eyes may keep me from having to shoot someone.  Of course, they will sue me for damaging their eyes. 

Frank