That's precisely why I used it!
Most forums have No Copyrighted Material policies so I'm glad that I was able to find something close because there isn't a whole lot of Callidus art out there (or if there is, I sure as heck haven't found too much of it). I
did re-size the fan-art (which was about three times larger) and tinkered around pixellating/sharpening the original's "brushed look" so it
would closely match the original (done in pencil/ pastel in the codex. It's a compliment that I came that close, given the base work. Being able to say, "I'm looking for the original like
this one helps people a lot more than a stick figure or a page reference!
Any ideas on where the actual Gallagher piece comes from?