Learning to use irons, and use them well, is a must. Things can happen that will put even an AimPoint out of commission. One of the biggest factors in a wet area like where I live, is getting the lens covered in mud. In a dynamic environment you don't have time to clean it off (this is where having a good QD setup helps. Now, you're shooting irons. . .GO!
There's ways to make irons shine, especially in CQB. I think everyone knows you can shoot accurately at range, but there's a misconception that irons are slower close-in. Let me submit to you that it depends on how you use the irons that determines their speed.
Try this: I like to take sight paint (I pick up orange the best) and paint the front post. But only paint from the top of the post down so that the paint covers as much height as the post is wide. Yep, a dot sight. Now, do some close-in drills. Don't worry about sight alignment, just mount the rifle like you normally would (you do practice getting a consistent mount, right?), and just put the dot of the front sight on the target where you want to shoot it, using the sight ears to bracket the target, and shoot. You may not be dead on (really depends on how consistent your mount is), but you'll be close enough. I find I can reliably drill a silhouette target in the chest to 50 yards accurately enough for a heart shot very, very quickly. Just as quick as a red dot.
The AR has another advantage here, in that you can paint the large ring in the rear sight a different color (so as to focus on the front sight, not the rear) and it helps your eyes automatically line up the sights with you still only focusing on the front. You end up with a sort of iron sight EOTech.
That being said, you also need to learn to use a red dot well, because they have their advantages. One, of course, is low light shooting, or on certain models, compatibility with NVGs. Another is for those that run a 4 MOA dot like an AimPoint. If you figure a frontal or rear view of a human torso is roughly 12 inches wide at the chest, and you use a 300 meter zero, then you use the 4 MOA dot as an ad hoc rangefinder. If the target is the same size or larger than the dot, simply hold dead-on and fire, and you'll put the round somewhere vital.
I think you'll find that while red dots don't have a speed advantage in the 0-50 meter fight, they rule as far as speed is concerned out to 300.

