Of the three versions you posted (B&W, colour and duotone) I prefer the original B&w because it is quite subtle, and makes you question what you think you're seeing (usually a good thing!). It is the simultaneous clarity/detail and subject ambiguity that appeals to me. The colour version reduces that ambiguity (and makes me wish you used a CPL), while the duo-tone is more obvious, but intrigues less, if that makes sense to you.