If you really want to do an epi-whatever fixture, I'd do Vipar(eBay) or MarsHydro/TopLED. A 180w actual light will cost about $150-$200 compared to $370 for the Platinum rebrand.What company would you suggest to do better on with the epi diodes?
Or, spend a little more and get 150w of efficient LED for $420 from Area51. You get a lifetime warranty, the ability to upgrade (at cost) as LED technology evolves.
Platinum, Lush, Kind, HydroGrowLED, Blackdog and GrowBlu (to some extent Blackstar) are ripoffs. A lot of money for epi-whatever diodes.