I realize this post is old and probably long forgotten, but I wanted to say I loved the variety in the opinions here. I did want to make one comment that makes a huuuuge difference from product to product. I don’t know all the brands mentioned in this thread, but I know most fondants are either Marshmallow based or Chocolate based. While statistically the chocolate based fondants seem to have better flavor and are smoother fondants, they don’t harden or dry out as easily due to the nature of the chocolate within it. Just like marshmallows alone marshmallow based fondants will become firm and dry, so the nature of that fondant will be drier. Therefor it is common to use Crisco as a moistening agent when working with those fondants but will dry back out after sitting.
