there is a chart in the LED forum, i saw, that indicated that a 5mm white led was still the lumens per watt champion. (depending on drive current)
but myself i analise it more like this.
each little 5mm led, has its own heat sinking capability, UNTILL you put them in containment, and clip the legs, and there is no air going across them :-( .
5mm leds are driven at SPEC for them, and they are not known for lasting a long long time, yet you can really pound a high-powered led and it will last a dang long time.
Nichita makes a kick butt led, it might not be the light meter champion, but it doesnt die as quickly, its not bleeding in blue, and as far as light output goes, isnt Color rendition more important when your trying to SEE things? so as far as Lumens per watt, you cant impress me with UGLY bright light, that is efficent.
High powered leds are, high Lumens per watt, ONLY when driven at the specs they are prancing around in the press releace, crank up the juic to the max for them, and they start putting out more heat than light, than they did when they are running low.
High powered leds, RUN at low power, should beat the snot out of everything, they have the phosphors, they can be heat synced and they are very efficeint when run at low power.
for time, efficiency, cost, and all, i would Much rather have a Great color rendition on a Very high powered led, properly heat sinced, and run LOW.
its all about the phosphors, THEY will die over time faster than the led die itself, THEY are the reason the white leds are efficeient.
RGB blows any white led away for seeing anything and everything, the color is amazingly better than the SUN, incadesescent , psudo white leds or anything, but it takes 3x that same ammount of power to get the same fuller spectrum light. so they are not efficient at all, but Really long life (not dependant on phosphor).
so that just leaves price
i guess.
large quantities of nice colored high powered leds, will last a long time, can be Dimmed, and dont take weeks to assemble an array of them, as long as your not Selling things (where having color is important) my money for area lighting is on any high powered led, well heat synced in huge quantities (so when you need light you got it) able to be dimmed down for longevity.
for sales, and stores, and other humans that hate stupid blue/white colors, RGB high powered leds.
