Have two similar chars, one is using DGS and other Scottish Halberd. Halberd is useful when backpedaling but that's about it. And has exceptional stab but it is so hard to hit anything with it. DGS on other hand has vastly superior swing animations, feels much much faster with same build and while stab isn't as potent, it is much easier to aim and can be spammed. If it had same damage values like Halberd, DGS stab would be incredibly overpowered.
tl;dr DGS much better.