Well, the ACOG because I'd love one for another rifle and their price tag makes them a tough expense to justify when you're only using them on things that don't return fire and one way ranges.
But on my VZ? The vortex red dot for field of view! My VZ rifle isn't sitting in a blind, or taking bench shots, it's being fed and made ready like the child of a parent with poor time management. Rock in the 7.62 nutrition it needs as its going out the door, and into action. (Read with Czech accent):"but father, I have no time for sight picture!!" (Heavier Czech accent):"Není čas! We'll miss your shot, put dot on target and make holes! Quickly now!"