The bottom one has the most impact for me, Kort... I think monochrome works best; but maybe it needs some more Shadow/Highlight in Photoshop to lighten the blacks and darken the whites... Then again, that could take away the impact it has.

We do not see things as they are. ǝɹɐ ǝʍ sɐ sƃuıɥʇ ǝǝs ǝʍ