We’ve had echo since it was in the first pilot phase and use it all the time. But we never ask it to do complex searches because we do those on our phones or tablets so we get the links. We have two different music libraries on it, multiple calendars, and lots of home automation stuff.
We bought the Google home and tried it for five days, then returned it. We had the following issues with it.
One) 360° hearing versus about 140°. The echo has nine microphones placed all the way around the unit. The Google has two on basically the same plane, so it looks like it was designed to be sitting against the wall. Our house is an open plan house and with the echo placed centrally it can hear us in about five different rooms. Google home had a lot more problems in this location, and basically failed to hear us from one side pretty consistently.
This was a big problem in our house, but likely not a problem for a lot of other people.
this is not my house, but it’s a similar floor plan. The kitchen is behind the half wall.
Two) Google home chokes on any **special characters,**even an apostrophe. With three housemates we have a lot of “Michael’s lamp” type names. Echo doesn’t like most special characters, but seems to handle an apostrophe easily.
Three). Grouping. With echo, you can put any device you want to go into any echo group and a device can go into more than one group. So since I say “study,” one of my housemates says “office” and one of my aides says “den,” it’s very easy to allow for all of these.
But probably more importantly is that we can create exactly the groups we want in a very intuitive way. As an example, I have a “turn all lights off” group that does not include One counter light in the kitchen or any of the lights on my housemates’ side of the house. it’s just very natural for me to say after getting into bed “turn off all lights” even though I don’t really mean all the lights in the house. 
Google home doesn’t have groups per se. They have rooms, but a device can only be in one room at a time and then it picks up all the devices in that room. And Google will try to guess what group you mean based on common words in the names for the device.
Lots of reports on the issues for these but we have three different ceiling lights. They all have “ceiling light” in their individual device name, but they are in different echo groups, so that didn’t matter. Google Home, however, decided that Michael’s ceiling light and JD’s ceiling light must belong to a group called “ceiling” and would turn them on and off together. It was possible for me to imagine a naming convention that would keep them separate but not one that I could rely on other people using consistently. This one was really the dealbreaker for us.

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We found the music search much better on echo. When you’re asking for things like “what’s the song with the lyrics that go…”. I’ve seen that mentioned by some reviewers and not others, so I’m not sure what makes the experience different for different people.
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we can easily play either of our music libraries from any of our echoes. At the present time Google home limits us to one. This was another dealbreaker for my housemate although I’m willing to believe that Google will add this feature later.
Similarly, echo can handle multiple google calendars while Google cannot yet.
- Google home’s command phrases for using IFTTT are definitely smoother since they don’t require you to say “trigger.” But it this point, we’re used to “trigger,” so that didn’t bother us.
Seven) we prefer having a name as an awake word. Again there are other households that may not care.
- **Multiple devices.**My housemate found that saying “OK Google” to the Google home would trigger his girlfriend’s phone when it was in the same room. The “will only trigger one device” pretty clearly means “only one device on the same account.” The same thing would happen with another Alexa device if it was also always listening, it’s just that there aren’t very many of those devices that someone would be taking to another person’s house.
I’m sure that the Google home’s management of music playback on multiple devices is much better than echo’s since echo doesn’t do that at all, but we actually don’t do that anyway. Small house, three housemates, if you turn the music all the way up in any one room you’ll hear it everywhere anyway. Which can be good or bad. 
- Google home is clearly a far superior homework helper for a kid who wanted to ask multiple lookup questions in a row. However, we just don’t use it that way. So while that’s an advantage for Google home, it wasn’t an advantage for our household.
You can see that many of these issues have to do with having multiple people using the device in the same home. And some of them are things that Google is likely to improve on in the future. So I’m sure there are many households where google home would be The better fit.
But for our household, it really didn’t work. Choice is good. 