From what I have READ online, the LED is what NASA uses to grow plants in experiments, for all right reasons. Super lightweight, no risk of fire, no heat buildup, no bulky, heavy ballast, no replacement bulbs... just the spectrum plants eat, too. Plants apparently have no use for green, yellow, or white light. When I think of how much power goes into creating HEAT, and WHITE in most grow lamps, the ultra-low wattage makes sense. I am of the opinion that they are really on to something.
That being said, let me also point out that most LED systems on the market are unabashedly, absurdly overpriced. The best bargain I have seen so far, and feel free to correct me, is the Sunshine Systems' GlowPanel 45. Obviously, uses 45 Watts. I can't see from the pic, but it looks like maybe more than 45 LEDs. It is $140. It claims to 'surpass 250W HPS'... cover 5 sq. ft. I can handle that price. But that UFO thing looks like a smoke detector with LEDs on it... and for nearly $600? I smell a middleman. I found the same object on a Chinese electronics distributor site, but price unlisted. The price just has to come down. I mean, aren't LED's supposed to be cheap?
I would like to know: Are these LED systems made of patented, photosynthesizing LEDs, or just off-the-shelf red, blue, purple, and amber LEDs in a certain ratio?
...because if that's the case, for $500 - I can buy those in bulk, and build a lamp that looks like the Close Encounters mothership.