get two light systems

[calif]

hi,i have a choice to get two light systems im not sure which is the best for growing, the stuff. the choice is between a 400w MH and 400w hps. THE OTHER CHOICE IS, 2,400w HPS lights. my grow room is 6' x 5' x 7' also should i spend the extra money for the agro bulbs?. the type of system i was looking at was the diamond lumenarc lll. dose anyone have any experience with these lights. will anyone recommend a lighting system. thank you.