Another way of choosing them if size and budget aren’t major concerns:
15 MP (effective) @ 75 mm? DP3
24 MP @ 35mm? RX1R
16 MP @ 35mm? X100s
16 MP @ 28 mm? GR or Coolpix A
They have similar image quality to begin with, and anyone looking at them are likely well-versed in post-processing to tune the camera’s nuances/colours to their own liking.
They’re further apart in terms of controls and operations, seeing how only X100s has a built-in EVF and the DP3 can be a slower (going by others’ opinions), but pragmatically none of them are committing major usability no-nos. Still, I’ll recommend testing cameras in person to see how they feel In (Your) Real Life.
Size and cost can be judged more objectively. If there’s already a strong reason why only the GR is affordable, then stick to it or wait for price drops/new products.
Hence, I feel it boils down to how much resolution one wants at a given focal length (and range for cropping). That’s the one thing that these cameras can’t change.