I like the ACOG with the flip up CQB sight. You get the best of both worlds, you can reach out easily to 400 meters then flip up the CQB sight an easily acquire targets from 0 to 100 meters. Throw on a gangster grip like Neil has (which by the way is in the wrong position brother) and you should be set. I've had the switch for the light mounted to both the gangster grip and the magazine well. Well the one on the grip was more convenient it did risk accidental discharge of the light.