yut, 1000W or 2x 600W huh...
I run one or two 400 watt in a 5' x 4' or less space (space is expandable to larger). I also have a (4) 4' T5HO luminaire which I use in seedling stage, early veg and later as supplemental side lighting. I find having the wattage flexible suits the grow better. Which one, my 1016 watt set up or a single 1000 watt? There are times when the 1000 W is the answer. If you can afford to have the supplemental lighting, and different watt sized lamps to swap around, or space for grow and Bloom then all the answers change.