I only bought a dot to try it out. I was skeptical because using Siri with my lights and AC units was clunky and cumbersome. Amazon echo, on the other hand, is legit. No waiting for beeps. As I walk into a room, "Alexa turn lights on" they come on. As I am walking out, "Alexa turn lights off" They go off. I get news briefings, recipes, and order essentials by just asking. My wife likes to ask about the weather as she is getting our toddler ready in the morning. It is so good at what it does, that I am going to be getting several more and a Harmony hub for my televisions.
Unless Apple has some killer feature that amazon doesn't have, I will be switching completely away from Siri/Homekit. Amazon is so much better at what it does.
It is also really good for adding calendar events and things to a shopping list if you use the Todoist app.