Well, for one I don't consider the alternative mentioned systems to be particularly useful. And I would strongly object to living in the same apartment/house as one.

I have not (and probably will not) research in what sense the privacy of this device is better but from what little I've seen it is at least better. And if not I can't imagine Anki being less trustworthy than the others.

I see it as a furby, which can be a little neat. Wouldn't buy it though.