I used 48", 40-watt fluorescent tubes for many years ... I got up to 12 tubes, when I finally switched to HPS ... the quality of the product is no better than with the fluoros, but the growth rate and yield is much better with the sodium ... fluoros have their advantages, primarily with even light distribution, and cooler running, but I am talking about the 48" tubes, not the CFLs ... I feel the CFLs have the disadvantage of 'spot' lighting, as opposed to the well distributed light of the tubes ... :smokin: