I personally would stick to Surefire, Malkoff, & Elzetta for mission critical situations like yours. HDS Systems is another reliable, high quality option if you want to get fancy. But, imo fancy is not what you want in a high stress situation. In this use case you need a simple light that always comes on in high and has no more then 2 modes(many prefer one). And, the second mode(should you want one)should be hard to get to so you cannot accidentally go into it when your life is on the line and you need high. Consider a momentary switch as well so if you drop the light it will go out instead of projecting your position. Skip the strobe too as they are pointless in most situations(more of a Hollywood kind of thing)and it is just another mode to accidentally go into when you may be under fire and need constant light.
Stay away from cheap overseas manufacture lights that lack potting and/or conformal coated electronics and ask yourself if your life is worth saving a few bucks. All things can fail but, in my experience the brands I listed are much more reliable then most(likely all) other brands on the market and that is why they are chosen by LEO, MIL, & Government Agencies around the world.
Sent from my SM-N975W using Tapatalk