"First the good: this box does a pretty OK job of containing litter if you have a wild digger or a high-tracking litter. Plus, it has a somewhat unusual/appealing design to it.
Now for the less than good: it does a JUST OK job of containing litter, probably no better than a regular box with one of those "track pads" under it.
The footprint of this box is enormous, even though the actual area for litter is pretty small. Also, because it's rounded, it doesn't fit well into a corner, or much of anywhere else.
The design of the box has led to one of my cats getting confused and regularly pooping on the steps instead of in the litter.
Finally, the compartment for the air filter kept falling open, until finally we just got rid of it.
We're going back to a more "traditional" covered box."