Elrond,
So far I like it a lot. However, I have only used it around the yard and adjacent woods. I ran some test shots with slide film to explore depth of field, real-world sharpness, and bokeh using the snowy woods as subject matter. I was also working on metering technique to keep the snow white. The results were fine for my tastes.
I recently bought a used Canon 200 2.8L, here on FM, to add a longer focal length. I shot some of the same tests in the woods. Holding the slides up side by side I can't tell the difference between the two lenses. I plan to repeat this using both lenses on the same roll of film in the same light, etc, and to project the slides to see what differences are evident. I am comparing the lenses just out of curiosity after reading so many "L" comments here, not to make any particular decisions.
Jay