It looks a little dried out around the edges to me (this appears to be a pet peeve of mine in photos of citrus fruit). Composition and focus are good though. Perhaps a little too green, but I guess that's the point isn't it...
Composition: 10
Technical: 10
Appeal: 10
Challenge: 10
Overall Calculated Average Score: 10, The nicest lime I have seen in a long time. IMO, a top 10 image.