Folks were wondering about the xiaomi mi a1 before. I've had one for a couple of weeks, and I'm very impressed with it.
It's well built, it comes with stock android that runs great on it. Strong battery life, and pretty fast charging. It's generally solid to use.
The mono speaker sounds pretty good, even at loud volumes. It's got a 3.5mm jack too, and it sounds good from my headphones. Nice big display, it's 1080p, but that's plenty good for me.
The fingerprint scanner is well placed, quick, and reliable.
The camera app isn't great (it's one of the only customisations, since it uses xiaomi's camera app). I hope it eventually gets improved, or I can use a similar one to the pixel one (I saw some people hack it on there, but it looks p complex, and it's not totally stable).
Because it's so slim, and the metal frame doesn't have the best grip, I think it's best with a case of some kind (I have ordered one). Physical home button would have been my preference, too. There's also no NFC, but I've never used that in my last two phones.
Great value for money, and it looks and feels like a phone that might have cost twice as much. Very little bezel down the sides, and comparable top and bottom bezels to an iphone 8 plus or similar.
I hope they deliver on the promise of getting updates for the two years. It's part of the Android One program, which means you get stock android, and a promise of updates from Google.
I gather it's exactly the same hardware as another xiaomi model, the mi 5x, so if you want their custom rom instead, you could go with that. I think you can also flash the other rom onto both these phones.