Its good. Last week in the Seattle area we had 105 F heat and the light temp was held at 102 F. Normal running temp is around 85 F. If I close the hood its around 96 F. I would attach a more current pic but if my "reef safe" fish was reef safe, I would have more corals to show off My powder blue ate 70% of my zoas. My yellow tang picks on everything. My hippo, well, he is "good". Anyhow, its good. If your still thinking about LED, check these out... http://www.reefbuilders.com/2009/02/24/sunbrite-led-system-hits-youtube/ These are going to be my new setup if the I5 goes. And they are cheap!
85 for the unit's internal temp a lot cooler than the "standard" lighting setups. Zero heat transfer to the water surface. You can put your hand under the unit and barely feel anything. Anyhow, I like the LEDs and their other benefits. Hopefully in a few years LEDs will be the new standard.