well do you need it stealth and silent and smell free? also what kind of ventilation you gonna use? u gonna grow hydro or soil?
its all in the details bro
i would go with the 150 in the middle (adjustable) and the two 70w on the sides for suplimental lighting, you should be able to grow a nice canopy in a 4' x 4' footprint.
gdluck keep us posted and more info = better answers!