A few years back I was designing light fixture PCBs on a contract/consulting basis for a local company that was (still is) in the Li-fi business, (wifi over lighting) and as such, I worked with these LEDs and similar LEDs from other vendors such as Philips. They are truly amazing devices but must be designed in with great care. There are far too many 2-bit companies slapping these things into light bulbs, auto bulbs, flashlights, and a hundred other applications, all without the engineering expertise to make them work correctly and over the long term. That is why I am so skeptical about the plethora of cheap (mostly China sourced) LED light bulbs now invading your local Home Depot and the web.
Most of those bulbs are really poorly designed from a thermal standpoint as well as optically. The LEDs have stringent power supply and thermal transfer requirement, and those are mostly ignored by the designers. I expect they will not meet their claimed lifetimes or light outputs over the long run, and some will die spectacularly, possibly even dangerously.
So you are talking to one of a very few PCB designers that actually has the expertise to make this work..... but frankly I dislike the idea.... and I'd rather just populate the fixture with lower wattage warm incandescent lamps and let 'er glow.....
Terry