Some info on these FGS shafts from DTG - they are all made by Integra using existing models of theirs, just rebranded for DTG. For example the FGS+ iron shaft is the iDrive Tour. The FGS 60 shaft is the iDrive Tour Lite. And the Vision+ is the Accuflex Vizion (Integra owns the Accuflex brand).
And yes the specs are slightly different for each of those shafts, but that's just done so they don't appear obviously identical on paper. But they are absolutely the same shafts.