Don't mean this to be controversial nor a flame, but why even pay any attention to a loaded chamber indicator? I say that for a number of reasons:
1) If I'm carrying, there's always a round in the pipe.
2) If I'm not sure, I check by racking the slide
3) If someone hands me a gun, I assume (in this case, it's valid to assume) there's a round chambered, so always check. I'm a creature of habit.
4) I view the loaded chamber indicator as a crutch and have never paid attention to it's presence or absence.
I'm curious as to it's use and value.