I don't own the black arcane gaff deck but I think I read somewhere on E's site or on their forums that the black arcane gaff deck looks a bit different from the regular black arcane deck basically. I believe that the white gaff deck is fine (I don't have that deck either but this is just from what I think I read).
I own the white arcane deck and gaff deck from Ellusionist. The two match up nicely and your audience will never know the difference. There is some inking issues with the black, so Id stay away from those.