I agree wholeheartedly with DansReef. To the people who use JUST Leds in whatever their config, I wish them the Best of luck, but you wont catch me doing it. As the Hybrid LED/T5ho systems become more widely available, and affordable, i am of the opinion they will be the "next MH". Mixing LED's shimmer, efficiency, and lifespan with T5's Reliability, broad spectrum, and performance will end up being a win win. Similar to the MH/PC combos that are still common and sold today. Once they drop the "snake Oil" sales pitch, and start combining the 2, i'll take another look. Led's themselves are still unteste/proven imho and are at least 2x as expensive. Untill the LED/T5 combo's dont cost 3x as much as comparable MH/T5, i'll stick with MH. Heat is an issue, easily dealt with. Cost of running metal halides, well if saving money was my goal, i wouldnt be trying to keep Reefs. I'd buy an ocean poster and Craigs list my tanks. Im a full time IT Tech. just because something's NEW doesnt mean its BETTER. I have to adjust with technology changes, but i have to stick with Proven technology even if its not the NEWest tech out there.