Been experimenting with the shimmer effect. My conclusion is that the Plex Shift type does a much better job than the Shimmer Verb type.
Shimmer Verb with Intensity at 4 (default) adds a reverb effect to the dry tone (as you demonstrate in the video), which I'm not looking for.
Also, the shimmer stutters, even with Diffusion turned up. You gotta turn up Intensity all the way to 10, to smoothen it (and it's still not smooth) and to get rid of the reverberated dry.
But even then, it's not as good as the Plex Shift, which sound much smoother, natural and offers far more control. And surprisingly, Plex Shift uses less CPU than Shimmer Verb, even with all its 8 voices. Check the Undulator preset on the FM3.