Man... I didn't notice this until now. But there are quite a bit of similarities between the aesthetic of the Duke controller and the new X1 controller. With the Duke being my favorite controller of all time (I have big hands), this excites me.
Look at the bottom of the handles - they have the same cut off. And in the semi-side views, they both have extreme slopes (more accentuated on the X1). And the "bar" area, where the Duke had that droopy area with the Start/Back buttons, is kind of there but without the actual droop.
What really gets me is the slope of the handle area, one thing I loved about the original Duke. It just feels great in my hands so hopefully the X1 will be the same. The new controller is essentially a mesh of all the old versions plus it's own new features.