What you have will work fine for veggin...veggin is not so lite critical and as long as they are growing and healthy, you don't need to worry so much about veggin lighting. Flowering is another ballgame tho. Buds like as much light as you can afford to give them. Two bulbs @2700K will give you loose leafy buds. IMHO there is no better flowering light than an HPS bulb (this will get some criticism!) There are other options, but if you want nice large tight sticky buds, you will have to get some kind of HPS (High Pressure Sodium), for 4 plants a 400Watt, for 6 plants, a 600Watt. Smallish plants will require less, but you can't really have too many watts! Watts are just a way to measure power, sorta like horsepower with cars...more power + more speed! Hope this helps