While the 1Dx gets the highest score of all Canon DSLR bodies, its sensor quality is no match for the newer Nikon bodies. In fact, the 1Dx “only” gets 82 points, the same score as the Nikon D3s available in 2009.
Here are some interesting comparisons (click for larger view):
|1Dx versus Canon 1Ds and 1D mkIV
|1Dx versus Canon 5D mkIII
|1Dx versus Nikon D3s and D4
Please visit the DxOMark site to read their full review or perform your own comparisons.