i couldn't do anything like this but... i don't like how the shoes seems blurry/out of focus while the mechanical elements are so crisp and sharp. The two don't melt together enough for me to believe the image concept.
I like it, but something about the area where your added elements overlap the white part of the shoe really bugs me. the engine inside the hole looks really nice, though.
nice manipulation with engine inside of shoe but this one looks like u were in a rush... u know..its great but not on the level i used to see from u