Ask a eletrical engineer. LEDGARDENER.com
The is guy brilliant. He responded to a email at 2am spent over 1hr walking me through a problem. There was absolutely nothing in it for him. Can't beat that. And he doesn't push any particular product line.
Check out LEDgardener.com. Great info,videos and he will personally walk you step by step through a build. He truly knows his stuff. Super guy. Not a tech snob!
LED is the way to go. Did the HID thing all through the 80's I gave up due to heat issues. Your going to love LEDs just be careful with the distance from plant to light✌