I have 2 tanks, one with MH and one with T5HO, and it is a striking difference how much more beautiful and happy all my corals are under MH, wereas the color and thriving is very low in under the T5HO.
I keep T5HO under my other tank because it is a nano and the heat would be hard to control, but nothing beat MH
I have pink and gold paly in my MH tank that are really gorgious, bright golden yellow in the center with very saturated pink tentacles, but when ever I sell frag to people without MH the polyps always become brown. Even those with LED cannot keep the pink and gold color! I don't know what's in the MH that give them that beautiful color but they obviously because very dull and brown under any other type of light.