Objective simply excellent. It has a little chromatic aberration between F / 1.2 and f / 2 and a slight vignetting at F / 1.2 and F / 1.4, other than that no complaints. Fuji is now in the big leagues, this lens is comparable to a Nikkor lens or a Canon lens.
The construction is very sturdy. All the rings are metal. Mine has seen snow, rain and sand and it still works like the first day.