Compositionally, I think the last one is the strongest, though I think I would have either rotated the bottle/rack counter-clockwise some, or moved it to the left (or both).
#2 also seems to me like it would look better rotated a bit. Like, roughly 15° counter-clockwise...
The last one is also the only one where I get a good idea of what the bottle holder actually looks like. In the others, the base doesn't appear to be centered under the bottle as well as in the last one. It's the only one where you can really tell that the two sections of chain are not parallel.