Bad idea.
Its use implies a few things that are absolutely wrong.
Wearing it and flipping it out, gives the user the false assumption that a responding cop sees it or even recognizes it.
Assuming anything in a shooting scenario or even with cops responding in force to what they hear on the radio that says "shots fired at so and so" has and will continue to get people killed.
Someone that thinks that they are safe because of this little gizmo and takes just a second longer to react to a command because they think "hey...I am a good guy and I got this little thingy here that says so, so I'm OK" can and will get shot by the time it took them to think that long.
And then...guess what...
you'll be dead and laying in your own blood with your little "I'm a legal concealed weapons holder" ID card flipped out laying right beside you.
A lot of good that will do.
