Unfortunately we will likely never see the 38 Super move beyond the competition crowd. Rimmed vs super comp brass, vs availability of either ammo.................. From a manufacturer's standpoint I imagine it's a steaming pile of nope idea.
But I do agree. The frame is big enough on the XDs 45 and it would've made an outstanding little gun.
However, same recoil? Me thinks my N105 loads are a bit warm then.