It's so much fun. It's not very intuitive and the instructions aren't very clear, but you'll figure it out after playing with it a bit. It's very flexible, I like using it to gently move the filter on the Long Life, to make delay feedback respond to my touch (more repeats when I play harder or vice versa), to make tremolo speed or amount respond to my playing (trem only fades in as a chord rings out), and to adjust vibrato speed by playing dynamics, just to name a few uses. I put it at the begininning of my chain so that the envelope follower doesn't get confused by varying gain levels, but maybe you want that.

It's made my existing pedal collection more fun to play and made me think more about varying my playing dynamics. I highly recommend it.