Mexico: Good thing you have pointed out... HEATSINKS!
I find the Chinese led boards regardless of wattage rarely have enough heatsink or even thermal mass. This goes for the plastic LED flexible-strip lights that are popular with RV crowd as well. LED + HEAT = short lived LEDs ... it matters not if it's one ten watt led or ten one watt leds or a hundred 100mW leds, the heat has to go somewhere!
Rule of thumb from a little company named Philips ... 3 sq in. of heatsink surface area per watt of LED. This doesn't have to be all on the horizontal plane, a heatsink with vertical fins adds a lot of surface area. Second thing to consider, surface area (fins) are only good if cool(er) air can move across them.
