We have an adapter that uses 20x5mm LEDs at rated power. Originally designed to use IR and UV LEDs, we have populated it with all kinds of LEDs, including white. At shows, we shine the 20x5mm light at a piece of paper and then shine our Trilight, a 3x1W Luxeon light, at the same target. The 20x5mm light disappears.
Now, some companies make products that drive the 5mm lights three or more times their rated power to accomplish a very bright light. We consider this to be a triumph of marketing over engineering, and while our company remains firmly in control of techno-geeks, that ain't gonna happen here. We like building products that your grandchildren will be able to use. We like building products that will work in emergencies.
If the nice people at LumiLeds ever get around to building a range of IR and UV Luxeon's, we will stop producing 5mm based products.