Which tone do you prefer?



The first image is my standard B&W conversion. The second one has a cool, slightly blue, tone I have been working on for awhile. I like it but am unsure if it looks a little unnatural. What I like about the second image is how the white of the clouds stand out.
Comments and opinions much appreciated.
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Cheers,
Paul.
EXIF DATA
Canon 1D Mk II. EF 17-35mm f/2.8L@17mm 1/250 f/16 ISO 200