For a lot of people this is the holy grail of 24mm lenses. But this particular reviewer is not so impressed:   "If a lens belongs to the Luxury series and we have to pay around 1700 $ for it is difficult to accept the fact that it might have some serious slip-ups. Unfortunately the EF 24 mm f/1.4L USM II didn’t manage to avoid them. The vignetting is simply enormous and to tell you the truth I was sure that the results of over 4 EV in this category would be only reserved for fast rangefinders’ optics, where short distance between the rear element and the sensor makes it very difficult to eliminate problems with light fall-off in the frame corners. We also weren’t very happy with the level of coma in the corners of the full frame."   Link