Definitely the black'n'white one. It highlights the beauty of the models, it accentuates the lines and curves. It even looks sharper than the coloured one. When in doubt always go for the B/W, it adds class and sensuality to your pics.
just looked. to my eye, this BW variant is better, given the lighting conditions. I wish you'd state who these models are. Both are lovely... and... my god what a perfect butt! Verily, it is THE Platonic Form of a Perfect Butt.
A very beautiful piece! And please tell your model to reply to me so that I know how to get my bottom to do that... *admiration jealousy* Very nice, love the poses here, and the clothing is very complimentary and unifying.