I bought my Echo Auto as an early access purchase in July 2019, so I've been using it for just under 2 years now. I have it hooked up to my 2012 Honda Accord via USB to the AUX input on my stereo. My car doesn't have a screen for Apple/Android integration or anything, so I just needed something "smart" in there.
What I like: 1) Navigation - I use Google Maps for navigation on my phone. Rather than hearing navigation instructions through my phone, I can now hear it over my car speakers, which is awesome. It will temporarily turn down my music to give nav instructions, like I would expect out of a car with a built in nav system 2) Audible integration - I listen to a lot of audiobooks through Audible, and being able to listen to my books while in my car is a godsend, especially for any long distance trips 3) Music - This can integrate with most music services (at least the ones I use). My primary is SiriusXM, which my car also has. I play through Echo Auto when I also need navigation; otherwise, I just stick to the satellite radio built into my car. But sometimes I want to listen to a random song on the top of my head, and Alexa will happily oblige! 4) Asking random questions - It has full Alexa capabilities, including the ability to ask random questions. I can also turn on/off lights in my house, lock the doors in my house, turn on my security cameras, etc. through my Alexa Auto. I usually remember to do that stuff before I leave, but if I forget, this makes it easy 5) Size - It's a relatively small and unobtrusive device. I keep it on a little rubber pad (that it came with) next to my cupholder. It doesn't get in the way at all
What I don't like: 1) Wifi to Cellular Switchover - Echo Auto uses your phone for internet (obviously). There is a brief period as I pull away from my house that Echo Auto loses internet connection: when I am just close enough to my house to technically connect to wifi, but far enough that I don't actually get any service. You can fix that by turning off wifi on your phone, but it's kind of annoying 2) Rare drops/disconnects - Fortunately, I haven't been cursed with frequent disconnects between my phone and my Echo Auto. But when it does happen, it can be very annoying. Especially when navigating somewhere unfamiliar, or listening to an audiobook or something. Again, this has been the exception rather than the rule for me (knock on wood)
Based on other reviews, this little device gets way more hate than I expected, at least based on my 2 years of experience with it. It's probably unnecessary for newer cars with Apple CarPlay and Android Auto integration, but for a car like mine, it was exactly the kind of upgrade I was looking for. $25 well spent, for sure.