Looks good to me, but the picture size is too small to really know.
Use photoshop or a similar program and reduce the quality of the image in favour of size. (as you won't notice the decrease in quality on a 100kb pic)
There's a lot of shades, highlights on this mini and also lots of rust in the metal area, see the claw from the behind and the backpack. Too bad I can't post a very high resolution pics here due to the space limit
;( Thank you for your comment !
Sorry, but I didn't quite find a link to your gallery. About the mini: I quite like the dirt, but most areas would benefit from deeper shades/highlights. esp. the metallic parts are a bit boring as it is. Rust or shading would be required, IMO.