Do people use red dots for close quarters stuff like that? Light and a lazer is what my friend has on his home defense gun, but his is a sig p365.
The AR pistol undoubtedly has a brace and inadvertently get used much like an short barreled rifle. Shame on you if that happens. Lol
Your friends sig as a true handgun is probably best with irons, light and laser. Though we do now have holographic sights small enough to be specially designed for mounting atop pistol slides and many are going that route as there is a huge advantage to plastering the dot as compared to lining up the notch, the post and the bad guy all at the same time. However there is a learning curve involved in the mechanics in getting the gun from holster to eye to on target.