Laser sights are a useless, wow-wee addition to a tactical firearm. I'm against laser sights for anything other than training purposes.
In a stressful situation that forces me to focus on the laser and not the target. Easy to get fixated on following the little dot around. Eyes have to continually refocus when the dot lands on a near, far, then near surface. Leading to a slower net time on proper sight aquisition.
Laser can get out of alignment.
Can run out of batteries.
Can break at the worst time.
Your laser dot shining on everything isn't a good thing.
In a dusty environment, that visible beam will act as a beacon right back to you (one can bet that in a tactical situation, one might be going against armed individuals).
Adds unneccesary weight.
The only place where a laser sight is shown in a tactical situation is in a Hollywood movie where we all know the true "experts" reside
Want to increase your quick sight aquisition and accuracy?
Practice, practice, and yet more practice.
I'm a big believer in tritium night sights. I won't own a defensive weapon without one.