ok here you go, best opinion you will get. I grow in a total of verticle 3' of space, this includes distance from light from floor of room. Very low ceiling.
Like to grow the white rhino, because for one it has a very short stretch and the yield is amazing. Check this link out, this is my grow journal at week 5, im in week 6 now. I also grow different strains and I am experimenting which handle the close quarters and light stress. A thousand watts at little over a foot away is extreme. My blue dreams are almost touching the roof because I didnt top them like I should have. There is many things to learn about LST in this situation. I was very ignorant in these areas and dismissed as unnecessary BS. But then I started an attic grow.........
http://www.youtube.com/watch?v=Q1dqDY_WQZY