Price, mostly. You can get Trident X, which is just as good of quality, at the same speed and timings, for less money. Theonly reason to get Dommy Plats is for a 2133mHz kit, CL9, at 1.5V, which doesn't really matter if your motherboard is worth half its weight.
I'm running with the hero at the moment. This is an amazing motherboard. Fan Xpert is extreemly useful.