Longnose as a former AI Vega user, I had a big problem with shadows/shading. Even with two units over a 60G cube, one side of a green slimer would be bright green and happy, and the other side would be brown and just sad looking, same coral, same location, just depended on which side was facing the lights. I believe that with LED's spread and coverage is the hardest quantity to achieve such that you don't end up with a lot of shaded areas, which is basically what dashiki was saying.
I went back to T5 with LED supplements. Sure LED has some issues coloring up a few corals as many have stated (even vivid aquariums will show you how their Pink lemonade is yellow under halide and green under Radions), but it does a fantastic job on most (probably a spectrum issue). I would say the greatest drawback is the uneven light distribution, which is why most tanks over 24" wide use multiple fixtures.
My vote, go multiple reefbreeder fixtures, there is nothing wrong with the reefbreeders, they just aren't quite as polished and dont have the terrific customer service, but they grow coral as many tanks can attest. Good luck!