I personally use the original amazfit bip. Cannot be newthough, I sourced mine from aliexpress, and even there they are ex-demo and stuff. Heart rate sensor isn’t amazing but I don’t know if that’s maybe my hairy arm. The main reason I got it, can be used with gadget bridge, for best privacy
Edit: worth noting that I had to flash it with English firmware, which did mean I had to use the official app originally