Dude, you will be able to grow 3 beautiful plants under 1 400w MH/HPS combo. There is NO need for 1 per plant. I grew 7 plants under 1 400w with amazing results.
Use the CFL's to veg, then flower with the HPS! I vegged for a month with cfls, then swapped to flowering with the HPS and my ladies loved every minute of it. The growth rate was also exceptional under the 400.
I was so impressed that im running 2 600W to flower, cfls for veg, and a 400w to start some clones in 12/12 from clone. Running a little test