And since it's true multi-color, it can refresh even faster by simply disabling the colors and refreshing in B&W (very slightly slower than monochrome screens though).
You seem to be suggesting "a collection of pigmented subcells similar to the traditional B/W cell".
ACeP works differently: the pigments are in a single cell, and it is a matter of different densities, size, speed, electrical sensitivity per material (per pigment) that determines the procedure ("waveform") to obtain the wanted colour in a pixel.
That was based on my tests with color displays from Waveshare, and as we have seen in the comments here, advances have been made.
I still see multiple refresh cycles being needed for colors. The metrics are shorter, smaller on the very latest displays, and in my view fall short of motion capable in color.
We do have, and have had, motion capable monochrome for a while now, given users accept a few trade-offs.
This is no longer true - Gallery 3 screens are ACEP that can refresh in a second and a half. For instance the Bigme Galy is an e-reader based on the Gallery 3, and [as you can see](https://youtu.be/V3jmmo23J5w?t=1202) is perfectly functional for interactive use.
It's still slightly higher than monochrome, but only by milliseconds. IMO, fast-ACeP is the future and will eventually kill CFA/Kaleido.