Its amazing.... for what it was made for. For me:
Build is adequate and not let me down so far.
Alignment fine so far apart from on second hand camera. Its close so I dont care and keep a wide attached to that body.
Optical performance is remarkable and the negs will leave you grinning.
Its not too heavy and ergonomically pretty good (not as good as the RF645 IMHO).
Lens changes are slow when in a rush. As a mobile travel/scenic/landscape camera it is without peer. FAR stronger in with slower more scenic people shots and action rather that faster in tight stuff, where I use 35mm.
All lenses are spectacular (of the main ones: 43, 50,65, 80, 150)
Have fun!