I really was looking for flight characteristics - I was also hoping there to be some discussion of the older discs that predated my time in PDGA.
I joined in 2000 and the disc I received was a yellow DX Cheetah, 147g, with a red PDGA logo foil. Immediately went on the wall where it remains today (and will remain, 150-class DX Cheetahs are a dime a dozen).
Something to keep in mind is that these discs only go to new members. The presumption is that most new members are relatively new players. Thus the disc is generally something beginner-friendly (light, stable to understable, etc). The PDGA probably doesn't have any specific requests about what the mold is other than that point (and apparently, that they're black).