It's hard to not temp myself with this lens. I own the 50A and 85A and am repeatedly impressed by their superb image quality. The 85 is still a bulk to handle, but it's worth it for the results and this lens shares much the same weight and build. I feel like I just can't give up on the 135L, however. I turned my back on Canon with the 50mm and 85mm with no regrets, but the 135's consistency with its autofocus accuracy/speed for motorsports, overall aesthetic, size/weight are just hard to ignore.
There's no doubt this lens has superior image quality in many areas and might have that little something extra that Art lenses just seem to have. But the aforementioned attributes of the 135L are also very important for why I own the lens in the first place...damn it...what a good problem for us all to have.
- Kevin