The 3DS version, because it has more shader cores and more everything across the board.
Both versions are pure cell-shaded graphics, but the 3DS has the best cell-shaded version of graphics because it can afford to make the cell-shaded graphics more cell-shaded looking, because it has stereoscopic 3D which will make the graphics more three-dimensional looking then the Wii version cell-shaded graphics in 2D.
At least wait for 3D screenshots of the 3DS version, before you make your judgement.
Plus the 3DS version is also the Definitive Version with stuff they haven't even mention yet, that are exclusive to the New 3DS version.







