i do kinda agree but 600w is good enough for a 6x6 room..but i guess its whatever..your more than enough light for sureThe industry standard says that for every 3 X 3 area, use 600W. I'd say your choice was perfect. A 1000W light is supposedly enough for a 4 X 4 area. I've always had mine on movers though.
plants can never get enough light look at the sun nobody can ever make a light as strong as the sun so dont worry about the plants just worry about the distance (from the plants and from the wall dont wanna start a fire) but sounds like a pretty good setup