I'm very curious to see whether the self-watering pot works. Are there any actual holes in the inner pot, or is the moisture in the growing medium dependent on only the porosity of low fired ceramic? Also what kind of ceramic is the pot made of? If it is natural clay, it should be fine. If it is a man-made "clay body" (artificial ceramic) it may be fairly soft and soluble and may overdose the medium with calcium or other minerals.
If the "self watering" process relies on the mere porosity of the wall of the inner pot, then a growing medium of only long-fibered sphagnum moss (which is what you're using, right?) probably (I'm guessing) won't be able to wick water efficiently enough from the walls to keep the medium moist enough. Long-fibered sphagnum tends to dry out very fast anyway, and with not that much nor solid contact with the wall from which it is supposed to suck moisture, might mean that you will have to water your self-watering pot most of the time.
But it's an interesting experiment. I wish I could examine one of those pots up close. Nearest Home Depot store is 150 miles away.