Very nice! I tend to think that Goldfish need over filtration anyways I actually have a friend who has a 60g with 2 Emperor 400s, an xP3, and soon to have a Fluval 404 set up once he gets the hosing for it. He tends to have water quality issues even with all those filters on it. I try to help him out whenever possible, but I think his main problem is over feeding.
i love how much u filter ure tanks! on youtube there's a clip showing the largest goldfish in the world! he is kept in a circular tub with crazy filtration because stronger water current promotes appetite, digestion and exercise which makes them hungrier, so they eat more and therefore grow more. i think you have the right formula...