First Impression - the most important one: Sexy wtihout being obvious.
Composition: I think this is where you could have got more points .. aiming to have a little more on the left of the picture to put the shoe on thirds - having a little more at the top as well. I am not sure how much you have cropped but that may have helped - just to give a little more of a line for the eye.
Subject: Meets the challenge with no issues about it.
Technical (Colour and light): I really like this .. I am glad you stated that these are the real colours - as I was thinking it was black and white overkill. With 24 hours going out and picking up something with more colour wasn't a real option.
To grow its vote?: As above - the cropping - or framing of the picture I think counted to the negative - but shot the person who gave you a one ... I can't see how!
Summary: Love it .. great shot .. .keep shooting.
If you've got any questions about this critique, please feel free to contact me via the PM system.