I had a similar question, DaMagoMan helped me figure it out, Although my mix was a 250 w HPS and a 400w MH, Basically try it out, I'm using both of them during the vegging stage atm and my plants are growing extremely well, no sign of any unhealthy conditions, I'm very happy with it so far.. But it also could be different depending on different strains..
Thanks for feedback guys! i am def gonna b using a light mover with two of these setups running. 2 400mh and 2 600 hps on a mover for even coverage of a 5 x 9 rectangle. Figure i will try a mix of 2 mh and 1 hps for veg then 2 hps and 1 mh for bloom! See what happens. i will keep u posted. White widow and Blue ice. 12 2 gal pots. 55 gal res. Advanced nutes prob sensi or Iguana. Rockwool on top of clay in each pot. Plenty of fresh air.