Like I said we're supposed to want what's best for our corals so why not put a light over them that you know will keep them alive and thriving?
I know for a fact LEDs will grow coral no problems. I'm not a halide user, so can't comment on those and maybe my opinion here doesn't matter because of that fact, but I am a VHO veteran of over a decade and successful SPS keeper for much of that time up to present. I can attest to the LEDs I put over my frag tanks growing coral far better than the VHO's I was using (same VHO lighting I am using on my display, just lousy maintenance on the frag tank) only thing I changed was the lighting and guess what the corals are growing faster and look more colorful than they did before.
It seems this thread is staying open just to argue mute points. If you like MH use MH. If you want to save electricity and not have the heat issues if they are a problem then switch to T5. If you want even less heat issues and more controllability options and even lower electric bills do your research and switch to LED
All three of these lighting technologies will fail if the user does not do their homework or buys crappy equipment. Do your homework and don't cheap out.
If you happy with your current lighting whatever it is don't switch!!! Focus on improving the other aspects of you hobby like maintenance and filtration. Lighting gets blamed way too much it is just that people can say Oh, I have the same bulb as so, and so ,but my corals look bad so they assume it must be some other thing they are doing wrong. With LEDs if something goes wrong everyone seems to blame the LEDs without first investigating other possibilities.
Sorry, I didn't mean for this to turn into such a rant but it's my opinion FWIW.