Test chart crops are now available
HERE.
Sorry to say that I don't trust their tests with wide angle lenses at all. They shoot a flat test target at very close distance, which is fundamentally not the way to do it. They even acknowledge this problem in their review of the Canon 17-55 2.8, and also in their description of how the tests are done.
Those test are meaningless, even for pixel peepers.
Real world images
here
Looks very very good!!
A nice set of pretty pictures, that would look equally good shot on a compact. They tell us nothing.
Sorry to be blunt
Have to agree that for the OP the Canon 10-22 is the best wide angle for landscapes, but if you don't need the width, Canon 17-55 2.8 is perhaps the sharpest wide zoom you can get for a crop camera, bar none.
On the other hand, landscapes are usually not very demanding optically, as you usually shoot distance, at a mid range aperture, in good light with a decent shutter speed or tripod.
In which case, pretty much any lens will give very good results indeed. You will perhaps see more benefit from using a polarising filter or a grad, or having a go at panoramas and HRD technique. Plus a lens hood.
