Only when silver aros a small do they have trouble with current. Once they a big strong fish, a strong current has no bearing. Since your talking a large tank you best bet for a filter is a wet/dry sump. I actually plan on using a wet/dry on my 350G once it's setup, and when I get the fish room going I plan to have multiple tanks on that sump.
You could also go with a multiple filter setup. My 180g which has my two silver aros in it has a rena XP3(canister)strictly set up for bio filtration and two AC110( hang on back)which are for mechanical filtration and have the sponges rinsed weekly. There are other members that go with the oppisite a run a fluval FX5(canister)for mechanical and emp400s(hang on back) for biofiltration. Neither set up is wrong or better, really just a matter of personal taste/opinion.