I've had a KMA-628 and I never got away with shit in 7 years of driving with it on. My father actually is part of a planning committee for the LA County Sherriff's department. He gets away with things because he has an actual badge, however, he gave me the plate frame and it hasn't worked once for me.
I was only asked once where I even got it when I was pulled over for speeding, and the dude proceeded to write me up for speeding, tint, excessive lowering, no front license plate.
There's no such thing as a magical get-away-from-tickets pass. In fact. I've been driving around with dealer plates for the past half year and I've gotten less attention than with my KMA-628 plate frame. I think that stuff just draws unnecessary attention to yourself.
Also, my friends within the Anaheim PD tell me of instances where people follow cars with those plate frames home and gun them down on their front doorstep. Either way, these plate frame's don't really do anything in the big scheme of things I think.