The data sheet mentions the temp specs, but it also says the specs are based on 2 oz copper. There is alot in the data sheet temperature wise, I didnt look in too much detail, but what struck me was the optimum light output, dosnt actually look realistic compared to the temperatures they give for it. Off my head I think 85C is max temperature, but heat dissipation figures given . Make me think that to stay inside the working temp, your going to be operating at a lower current than the one that gives the best output.
Or I guess your going to have to get creative with the heat removal. the other thing was they make a big deal out of not using tweezers or fingers, it reads like its only suitable for precise size suction pick and place. But they could just be covering themselves. I dont know Flyback I havnt used silicon coated Leds, but they do mention the outer material is not like normal leds etc etc etc.
Whats the application? I cant help thinking you might be better with a ON semiconductor Led, they do some good high powered Leds. If I get a chance I will read the datasheet properly, it was a quick read but gave me a gut feeling the temp figures need a close look at.