Pro-4000W

I'm very pleased with this light. I have yet to push it pasted 80% of power. At 33 sq ft of grow space it is great for flowering. It does put off some heat at higher settings, but that's not a bad thing when outside temps are low. I also have two smaller lights to boost the side areas of my space. I think this light would be all you need for a 4'x4' space. It could handle a 5'x5' space but you may see some degrading at the outside of light area. Cost isn't terrible. The weight could be a little less. The mounting harness cable could be shorter, or a different design, because you loose space when you lift the light to full height, but over all 9.5/10.