I would agree...isnt there supposed to be some sort of span to vertical support ratio? The weight of the water in the tank will be pulled down further between the uprights than at the corners...I would think in an aquarium situation, flex is never wanted, ever. Not even a little. Thats why stands need to evenly distribute the load especially in the center of a long tank. Whats good for the corner uprights should also be in the center. Maybe thats the "overbuilt" factor of DIY but I think with 200-300+gallons in my livingroom, I want overbuilt and am willing to pay a few extra bucks for it.