Ladies unt chentlemen, ve haff a veener!
With an MTF chart like that, there's basically nothing left to complain about. Sure, it's only f/2.8, but so are the 16-35, the 24-70, the 70-200, and the fast supertelephotos. "Only" f/2.8 for a lens with this image quality, this size, silent full-time manual autofocus, all in a package hardly bigger than its rear lens cap?
Sign me up!