I have somehow managed to accumulate three Supersoft Wizards and one Soft Wizard, and a whole lot of DD putters in Classic (hard), Classic Blend, and one Prime Deputy.
First, with Gateway, "Soft" is anything but. Soft is more firm than Classic, by a lot, for the most part. "Supersoft" is more in the range of Classic, and Supersoft is more firm than Classic Blend.
I should note that Classic Blend can be pretty firm fresh out of the box, but softens up fairly quickly with putting and/or throwing use.
Second, Gateway's plastics are good, but are all over the map in firmness. SSS can be pretty firm or relatively soft. Supersoft can vary from run to run, from as firm as Soft to as less firm as SSS.
And third, and just like flight numbers, the "softness bar" should not be relied upon with Gospel certitude, so sorry. Especially when talking Gateway plastics.