For spotlights, flashlights and other purposes that benefit from a quite directional light, this is good. It even works well in situations like traffic stop lights and vehicle tail lights, where the combination of a directional light source and a custom designed lens can provide any specific desired lighting pattern.
But it doesn't work so well for residential room lighting, where one usually wants a broad, minimally directional, flood lighting pattern.
Most reports that I see that brag about how efficient LED lighting is are done by measuring the light that is output at one place, right in "front" of the light. They don't account for whether the rest of the room or other lit area is in relative darkness, or lit with similar brightness.
they produce less light than the bulbs they are alleged to replace. They also have a different spectrum even though they have ~20 LEDs of two different colors.
I tried them outside in the winter and found that they are better than CFLs, but not as good as incandescents.
LEDs are probably the future. CFLs an interim solution.