I have a 4x4 and i currently have 3 sf1000’s running, and just ordered a vivoson 1000, the cheap one with no dimmer. So every 4sq feet will have a 100w full spectrum board. Now being like $450 into lights i wonder if i would have been better off with one large 400w light? I mean the only clear advantage i can see would be the ability to set all the lights at different heights.
And that could be a plus!!
This really comes down to performance and design of each light. A more diffuse light source is generally better, but several of the large lights are designed in a way to produce this. First priority should be getting proper amount of light into the grow space, then getting light intensity levels as balanced as possible across your canopy.