In the conclusion they write:
Once more Canon delivered a a high performance lens with only a few weaknesses. The center performance is very good at max. aperture and excellent to downright superb at medium aperture settings. The borders are somewhat low in contrast at f/2 but very sharp when stopped down a bit. Lateral CAs are next to non-existent and distortions are pretty much irrelevant as well. The vignetting is nothing special though so you have to live with a high light fall-off at f/2. Canon was able to fix the bokeh issue that plagued the old EF 35mm f/2 – especially the critical background blur is very smooth now and better than most lenses in this focal length class. You will be able to spot some bokeh fringing in critical scenes when shooting fully open but that’s a typical behavior for such a fast lens anyway.
There is more to read, obviously. If you are on the fence for this high performing lens then be sure to check the review.