Here's a review at
photozone, though it's on a cropped camera, not full frame. Looks stupidly sharp. And no obvious weak points to speak of. I also wouldn't down play the importance of build quality and the
advantage of manual focus. If you enjoy using solidly built, well crafted lenses, then that should be factored into your purchase along with image quality. I own some old MF lenses and they are really fun to use. It's my hobby, after all, and it's supposed to be fun!
Also,