Part of me wants to buy a few and put them in different parts of my house so I don't have to yell through the house when I want people to do my bidding. How do you use them? Do they work? What do you like or not like about them.

I'd like to hear arguments pro or con about why they are great or about how they are going to cause unending misery through privacy breaches. Note we are all iPhone users in my house, in case that makes a difference.