I will pick the 2nd one despite the imperfect crop. The pose of the model in #1 is somehow too relaxed, it's rather like a candid behind the scene shot. On the other hand, the overall feeling of the 2nd shot has a very dynamic power from the contrast between the slowly dropping cloth and the tension created by the model's pose. Take analogy to music, this is just like a very sudden and dramatic stop after a melody of very fast rythem was played. I really enjoy the atomsphere you've created. However, personal feel, if a more concetrated spot light was used, it may be even better.