I rented an X-Pro2 to try it out for night photography. The new sensor is absolutely wonderful for night shots, gathering a ton of detail and color. The focusing is good on anything that's even slightly illuminated. Focusing on bright stars, I noticed it missed focus slightly about 50% of the time.
I attached a sample, view the others on my 1x.com page
https://1x.com/photo/1187220/all:user:592739
https://1x.com/photo/1188080/all:user:592739
https://1x.com/photo/1188087/all:user:592739