the most i can figure, that i've noticed at least, is the stamp of the disc. I've thrown two identical weight destroyers. one with the factory stamp and another with a tournament stamp, with lots of foil on it. the factory stamp was much more stable than the tournament stamp. same with two wraiths that i have. i think the foils stamp affects the dome just enough to make that difference
Do different colors of the same disc fly differently? Yes but not in any predictable pattern. And the differences may be so small they don't matter.
The new drivers with wide rims and sharp noses ( Force, Surge, Destroyer, Boss, etc) are the most noticeable in terms of flight variance. Putters are the least noticeable. The more advanced in skill a player is the more he will notice the differences which are there. A beginning player will spray shots in unpredictable ways no matter what he is throwing.
Discs are made from plastic beads. Different types of plastic beads are blended together in a single disc. Color additives are also added to the formula. When color is added to a disc formula, it changes the total ingredients. Just like if you were cooking a dish of food, small changes in the ingredients may change the end result dramatically or the change may be irrelevant.
For any given run of discs, the different colors may change the disc's flight a lot or so little we can't notice it.
Within a single run there will be a degree of consistency within a color. So if the blue ones are overstable, then probably all the blues ones will show that tendency. But for the next run of the same disc there is no guarantee the blue ones will also be as overstable. So if you find a particular disc you really love, try to get more of the same color and same run.
From testing many prototypes and many runs of Discraft discs I have never noticed a clear pattern of certain colors showing certain tendencies. So the orange ones may be flippy for one run but stable for the next.
Since most players throw candy or candy blend drivers, the minor differences in runs can work out to be advantageous. Find a mold you really like. Buy several of that mold in different colors from different runs. There will be small (or maybe even pretty large) differences in the flight characteristics, which with practice you will learn to recognize. Since they are candy plastic they will not change for a long time.
Personally, I love Crushes, Flashes and Rogues (my primary overstable, stable and understable drivers). I try every new run of these discs to see how they fly. I usually have multiples of these molds in my bag and I want them to be a bit different so I can shape the shots I need.
I'd definately say true...I can throw champ sidewinders better and truer than I can with the star plastic...and a good example of colors, I've seen the Boss fly incredibly different with different colors...it's kind of odd, but this is very true in my opinion