one things for sure,make sure your ballast is ok running different wattage bulbs,their not to happy when they've been made to light 150w and you change to 80w(also a ballast made for mh will find it hard to run a hps(some dont work at all)).you also want the higher wattage bulb to be the hps(mh for veg,hps for flower.(you can get away with cfls in veg).more light in flowering stage=more buds).good luck!