I really do believe that the response of teh 3k's keys is better than the 2k, and 21k. I'm not sure if it's downward throw, or stiffness, or both, but the 3k is more friendly to my hands than the predesessors were. I don't care what the book says ..... it's different somehow...... then again, my psr hisses.
(I think it's the internal effects because I play rhodes sounds mostly, and as soon as I touch the keys, the hiss begins.