Looks pretty cool, I would imagine that they are pretty expensive though.
I have replaced virtually all the halogens in my house with LED lamps, and my last leccy bill was down by over 30%

( I replaced about 28 halogens )
LED's are the way to go, once the price comes down a bit more as production goes up, then it'll be a no-brainer to have them instead of the halogens.
Tim