I have come to the conclusion that lasers on your carry gun are important. Besides the odd movie theater massacre, most bad things that might happen to you are most apt to occur in low light situations; even in your home.
I will agree to a certain extent, My LCR has horribly invisible sights in low light so the laser on that revolver is very helpful to me. The laser is plenty accurate from 5-17 yards (for a human sized target) It is actually sighted for 7.5 yards but the laser is still accruate enough at 45 feet aiming at center mass (with a SD load), if I am 50+ feet away from the threat I am mostly trained to retreat to a defensible position if possible.
In the same low light I can see the sights on my Glock and Beretta 92FS, so a laser is less important on those guns.