Led lighting

Has anyone used and had success with this type of light? I'm curious b/c it would cut down heat drastically as well as be cost efficient in terms of electricity usage vs MH/HPS or T5 fluoro lights even, hell even better than CFLs. Just thought it'd be a good question to ask considering Nasa wants to use LEDs for a space farm.

Lettuce and LEDs: Shedding New Light On Space Farming

they are alright a buddy of mine used am, but do not match the hid lighting

i've heard you can veg alright with them but nothing impressive, but for flowering they were dismal.

thnderchunkie does a full grow with them in his journal. you should look it up

I'd love to give one or two of these a try when I have the cash.