Different colors require different amounts of pigments. I've always imagined that the properties of different colors could not always be the same. I just purchased a CR-10 V3 and have yet to set it up. To start with I have purchased rolls of black, white and red PLA from Overture and 1 roll of black TPU to test things out once I'm ready to start printing. I am probably going to need to try a different brand in the same colors just to see the difference. That will be after another month or so of reading the forums to learn as much as I can. I have seen some value packs of mixed colors of .5kg rolls. That might be my next step.