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Sort of the same feeling here, for looks go CL. Had a 75g with three MJ1200, didn't want the same on my new tank. Just mentioned the Streams as you seem concerned about efficiency and flow. Since it sounds like you are placing the CL pump below the floor rather than in the stand you'll be cutting down on noise.

My CL pump is a Dart and it's below the tank. I still notice it when the house is quiet (can hear it humming now) even after the tank setup for months but if the TVs on or just talking it disappears. I considered having it in the floor/ceiling joists space directly below the tank but then it would have been where the HT is going, wouldn't of last there.

I have 75g sump and about 1000gph, seems totally fine. With my old pump could have 2000gph but restricted the pump back mostly because discharging that much back into the tank through a 1" pipe I was getting splashing and placing stuff was difficult. Going slower definitely found I had more crap settling in the sump.