10x pro plastic CE

Anyone have insight to the real story behind the 10x plastic used for tbirds and other drivers.
I have several 10x tbirds and the plastic varies between hard/clear ce plastic and a tackier version that isn't clear but isn't regular pro plastic either. Not to mention colors.
I was just wondering if someone knew the story

[wootang]

From what I know it seems that the later or last runs of the 10x drivers were a blend of pro and champ plastic. But the older first 10x runs were the same plastic as the 9x driver which can beat in quickly with hard hits like bending the nose of the disc and the later mix(blend) run is much more durable.