This is a granular drum sampler I'm working on in Reaktor that has Elektron MachineDrum style parameter locks. I think it sounds pretty good so far. Note the ridiculously low CPU usage - 2 percent, not bad, ey?
At the moment, the knobs are used to write looping parameter automation per step, and this works great with Kore 2 hardware controllers, but entering percussion sequences must be done with the mouse. I've tried using a MIDI keyboard to enter data but it's hard and fiddly to get the exact velocity you want on a given step, and a pain to remove steps.
I'm going to wait till my Maschine arrives and use its drum pads to trigger sequence entry. The sequencer doesn't send MIDI yet, but the controller does and from everything I've heard it's a joy to use.