In this case at 28mm the comparison of both standard zooms from Canon and Nikon is clear. The Canon, let's say "my" Canon is very slightly better than "my" Nikkor.
The standard zoom from Canon is generally recognised as one of the best zooms ever built. I had a Leica R8 but never could put my hands on a legendary Leica Vario Elmar 35-70 mm f1:2.8 and the few owners of this lens talk marvels about it although his price belongs to other world not to this one.
Facts confirm, anyway, that pictures taken with either of these standard lenses are wonderfull. Both are big cannons and with a pro camera with motor the weight is out of reason but results are excellent.
No doubt that to use these kind of gear makes the photographer the only responsible of the mistakes as either the camera and its metering and focusing systems are excellent and the lenses too. But remeber the great pictures are due to the man never to the gear.
