growing the budz is exactly right.. the more lumens that a plant gets, the bigger the plant and therefore the buds will be.. this is why people prefer hps and mh lamps compared to cfls and other types of light.. hid.. high intensity discharge bulbs such as hps and mh put out more lumens per watt than cfl lights do.. what this means is that a 250 watt hps will put out more lumens than a 250 watt cfl will..
now saying that, cfls put out much less heat and can therefore be place closer to your plants than either an hps or an mh bulb.
many people have great grows with all kinds of lighting.. hps, cfls and mh.. they key is just make sure you have plenty of lumens getting to your plants, regardless of what type of light you use, the more lumens, the better your end result will be..
hope this helps you out some