We'd suggest aiming for a light that can emit at least 500 lumens; that usually covers most scenarios. You'd want a pistol light that can light up your surroundings effectively, depending on whether you're indoors or outdoors. But remember, lumens just measure the light an LED produces. The real brightness also depends on the design elements of the light, like the reflector's size, and how clear the glass is. Sometimes, a top-notch pistol light with 500 lumens and excellent reflectors and glass can outshine those boasting higher lumens. So, focus more on the light's actual performance rather than just the numbers.