It's not bad at all . If you simply had erased a bit deeper around those arms and then experienced with the blur tool to make them blend in with the rest of the picture (perhaps with the contrast tool as well) this would be an excelent fake .
I share the same opinion as Zerit on this, if you had found a way to take a bit off the extremeties of his arms, it would look more real, but this is all good as well thanks!