RE: When it gets dark....
My cobra sidewinder gives plenty of glow on the green pin till just about 1/2 hr after sundown, with the tru glo pendulum I quit about 10min. early. Seeing the pin is one thing but seeing the target is another. In an open field it's no problem in the dark woods you're done early. No point in taking an unethical shot! The lights built into some sights just make it harder to see the target IMHO.