The olight has relatively old features compared to nowadays flashlights. The lack of regulation is one of them.
I would get the RRT2 instead, it uses an R2 emitter, good regulation, can take 18650 or CR123 and has the ring switching mechanism which IMO has a great advantage over the clicky. And the throw of this one is amazing.
If you want a simple 2 mode not so expensive flashlight you should consider the Fenix TK11R2. Or even cheaper yet, with almost the same construction quality and brightness, the Eagletac T100C2.