I recently replaced 3 traditional incandescent lights with 3 Intellibrite 5g color LED's. Yes, they are not quite as bright, but not by a huge margin, and not to a point where I think its too dim. The color changing shows and ability to change up the colors based on mood, etc is really cool... definitely adds a blingy wow factor to the backyard. I think my only complaint is that the "white" setting on the color light doesn't look like the traditional white lights I replaced, it has a more blue artificial feel. I don't know if the white only LED lights have that same look. They did cost more on the front side, but my lights turn on at 7:00 and stay on till midnight, so I feel a lot better about the 3 lights using less than 160 watts total, vs nearly the thousand watts they used before.
With all that being said, if I had to do it all over, I would definitely go with the color LED's again.
-Sean