On mine, I am using the P-37D keyboard, and in fact the whole internal works of the P-37D. So there’s no difference in the keyboard action. But the sound is quite different, which must result from the enclosure, the different plastic and the absorbant strip. I’ll be interested, though, to hear what you think of the P-37D when you get it, Frederic. But the key action may be affected by air pressure resistance with the P-37E. I think key action is generally tighter on Yamahas than on Suzukis or Hammonds.