The SC3 Pro is the feel-and-build reference, topping our fidelity and build axes; the Podium DD1 is Fanatec's 20 Nm flagship with the QR2 ecosystem and Xbox support, and it is the cheaper of the two here. So you are weighing outright signal quality against ecosystem breadth and price.
On PC, chasing the best feel, the SC3 Pro is the pick. If you want Xbox, the Fanatec rim catalogue, or simply to save $240, the Podium DD1 is the sensible flagship. Both are proper top-tier hardware - the split is platform and feel, not a value gap.