very nice ^^ i like youre style . But in the second and the third you lighten it to much cant see the sig good anymore ;(. For the rest it's awesome...
All of them are good, but the lighting in the second and third are really taking away the good tag...Plus your renders are really dull colored,try messing around with gradient overlays, or sharpening your image.
i agree thats defo my favourite. love them all. second third as its been said too light, brightness/contrast will sort that out.