Appreciate the input. I agree with everything you are saying. My opinion is it would make a good 4x4 tent light but 5x5 is pushing it a bit. That being said, most of the ~400watt lights don't quite make it for a 4x4 and the ~640 watt high output lights are a bit too intense in some spots for the 4x4 area. From my looking the other light that closely fits the bill is  MARS HYDRO FC-E4800 480W COMMERCIAL LED GROW LIGHT. Similar price, lower wattage, but over a 4x4 area looks like a very even illumination in the right intensity requirements.  I'm still shopping but I probably wont make a decision until late December (my wife  complains that I take too long researching everything I buy, to the point I miss good deals while I wait and look. LOL).