Both are very good, but I'm more partial to the black and white version, I really love the soft blending and shading over the bolder color and forms of the colored piece.

The color piece the main figure is the center of the work and very distinct, in the b&w the background has more focused equal or greater, as well all the details are very strong. For some it might be more 'busy', but I like it. I keep seeing new things and rediscovering details.