I have a 4' 90 gallon and was not that impressed until I mounted under the top center brace and went to the alternating gyre. Now I love the flow I am getting. Also all three sides are open to view. You don't even notice it up under the center brace.
Up that high, you don't have any problems with vortexes/pulling air bubbles from the surface? Is your rockscape solid across the tank, or interrupted island-type?

