I find them perfect for a close range defensive handgun, which is really what a handgun is for.
I wouldn't put them on a long range target gun but that is not what I have Glocks and 1911's for.
Also I think it is not a good idea to think that you won't use sights in a close range fight.
Looking at the front sight is a sure way to make that first shot count.
I practice both point shooting and quick front sight shooting and actually sometimes miss or at least not hit where I want to hit when not using the front sight.
Big Dots are perfect for what they were designed for.
Close range gun fights.
With a little practice they are capable of long range work too.
All a matter of shooting them a lot and getting used to them.
I've had them on several of my guns for a long time and I don't plan on changing them.
The Evil Captain Kirk