Just my opinion here.. But a 400 watt HPS/MH setup would be cheaper upfront. I know heat is an issue for you, but with a inline fan blowing through the hood I hardly have a temp issue. Once I figured out I would need some 20+ CLFs to get the same lumens per square foot suggested, the total watts was just under 1000 - that is on top fans etc. Really though it depends on the total square footage of your grow room. You can get nice sets on ebay for decent prices.
LEDS are rather expensive, and as with anything you will need enough to give decent converge to your entire area. LEDS and CLFs from my understanding give smaller yields, but they do have their benefits also.