It's very difficult to judge the internal build quality by looking at the photos of Samyang. The Canon TS-E 24mm II is a mechanical tour-de-force in how precisely and surely all the tilt and shift mechanism work, along with how the optical elements line up optimally even with heavy tilt/shift. I would be hesitant to be early adapter due to unknown durability and continued smoothness of all the mechanical parts. Then again, some years from now, if the Samyang users still report good durability and optics, by all means I am willing to give it a shot.