prolly not a bad idea...150w would give you 50w per plant....thats not bad....and youll see better yields and quality using the hps over the cfl's..........do it, i dare ya..lol
i wouldnt even bother putting cfl's under them during flowering. just use the cfl's the veg. when its time to flower use your HPS (400w for 3 wold be prime) and mabybe buy some 2700 kelvin cfl's during flower.
ya i want to but im worried it will get to hot in the area because it is in a closet that i lined with mylar. i do have a rather large carbon filter in the closet thats like a fucking jet engine and might make the room cooler what do you guys think?