_sem_
It doesn't make sense to talk about long key sticks as if that increases leverage. It doesn't. The leverage is decided by the distance to the balance rail. On this new action the distance isn't the same as it is on a concert grand.
Acoustic grands are much more complicated. In contrast to the Casio GP action with one more moving part than a typical DP hammer action, this one seems to have one less moving part, so no hammer. Hammer actions have a gear ratio for the hammer. This one doesn't; it only has weights on both sides of the stick. They must be roughly balanced (so that a ca 50g of weight on the tip of the key gets it to move down). A longer distance of the weights to the balance rail (on both sides) does increase the inertia (torque). Due to the lack of the hammer, they also need heavier weights to get reasonable inertia. Expect MP11SE kind of portability 😉



