Best bang for your buck for a closet type grow would probly be a 400w HPS... it will use about the same as your refrigerator for electricity.. and will give you proper light for 4-8 plants depending on strain and how long you let them veg for. HPS works fine for veg and bloom.. some people use Metal Halide for veg... but Ive found this to produce thin wimpy stems that just cant seem to produce as well as the thicker stems when using HPS. LED will use less power.. but in my experience.. less power = lower yield.