Seio Powerhead Reccommendations

[TheReefGeek]

I am thinking about trying some Seio powerheads instead of my closed loop. I like my closed loop, but have never tried the Seio/Tunze style of powerheads and would like to experience the kind of flow they offer.

My tank is a 180g, 6x2x2

Should I go with 2, 1500gph models, one in each corner? Or a single 2600gph model shooting across the tank?

I like the idea of a single powerhead because it puts less clutter in the tank, and I could build my rockwork such that it is hidden well. But is this flow going to be enough?