Hi Stragu! I'm using the MapWithAI plugin in JOSM to start with the Microsoft AI buildings, but there's still a lot of work to straighten and adjust them to fit (generally) the Bing imagery. I then merge them with the address import (which I am not a fan off, but anyway) and then head our with Street Complete to do what I actually enjoy. Happy to grab a coffee or cake sometime if you want a demo.