I use the small precision Hering "Blues" which is black box plasique. I think it's one we are referring here. I have two, one in G and the second in La.
What characterizes this machine is its weight. This is the 10-hole diatonic pus heavy I know. So there's the matter! I admit I was excited about the first purchase was the Sol. He's a hell and alters beautifully. Unfortunately it seems that the qaulité is not a constant CHRE Hering (you think?) Because the second purchase is not tight, stiff as a blade of justice and sound away from the superb first.