I wont get into the back and forth other than to offer my observation. I had metal halide for years 3 250mh to be exact on a 300. I wrestled with the led thing for a long time and I mean along time about 2 years before I found some that I felt deserved a shot. I have never seen growth on my coral like I do with these leds. I for one will never go back to mh. The lack of heat (although they run hotter than I expected), The ability to more closely mimic the sunrise/ sunset , no bulb changes , and the ability to adjust the "color" to my liking just make them a good choice for me.