I have had phenomenal growth rates in my predominantly SPS system using DIY LED's (96 3w emitters) a mix of 4 whites 4 blues plus red, green, cyan and now violet. Coral growth lighting wise is rather affected by overall spectrum and does not matter the source LED/MH/Flo. Corals will be healthier and grow more quickly in a full spectrum 10-12K range than in a narrow spectrum 15-20K range, though they (some) look amazing with their fluorescence. My original research going back 4+ years in creating a mix of emitters that emulated the Phoenix 14K lamp without much so-called garbage light that is always there with incandescent bulbs. This was the data used in my own build as well as Eric & Beccas, Mojos and now several others out there. It provides a crisp blue-white light that we see yet fluoresces more than just the greens and oranges typical of 20K MH or Cool White / 460nm Blue LED fixtures. You or anyone seriously looking into building your own or buying a multi spectrum LED fixture like OBD's are welcome to visit if in the area.
Cheers, Todd