DxO Labs has tested the Nikon D610 sensor and has found its performance equals the D600. Minor differences may be accounted for in margin of error, further indicating that the camera is nearly identical to the model it replaces. They make no conclusions about whether the shutter change will solve the apparent dust and oil issue of the D600.
The Nikon D610 is well ahead of its competition in the Canon 6D, besting it in dynamic range, color depth and high ISO performance. Overall, the D610 scores highest of any 35mm DSLR except Nikon’s own D800 and D800E.