I would contemplate 2x maxspect units for the punch and coverage abilities. you might be stretching the capabilities for coverage with 1x unit. I have 3x units over a 36" tank and could have easily gotten away with 2x units, but am really happy with 3x units after running them for the last few months. I put 40 degree optics on the end rows to contain the light, lights are 12" above the waterline. light spill was a big factor in my decision to change over, whereas my tank is in the same room as my TV. I can tilt and move the panels for optimal coverage and point to coral formations in the tank. I think this feature would be important to you since your covering a cube, and not a rectangular tank, i.e. one light all the way forward, one all the way backwards.
I can't comment on the radions or the AI sols (have heard positives), never used or seen them, but tickled pink with the robustness and flexibility of the maxpsects. not a big fan of the controller, but it does what I want, ramp up, ramp down.
there's a lot of marketing and hype amongst the manufactures, some do a better job than others...keep that in mind when you post questions like this.
you'll have fan bois of certain products...even without any actual experience using the product.
good luck!!
C