Well, I have also been looking into this and I am planning on LED. I was originally planning on DIY, but have recently been leaning more towards just buying one because from what I have read LED fixtures are pretty involved to build.
Also, I have a freshwater setup without live plants - so that might decide what you need.
What I am leaning towards now is this
http://www.aquatraders.com/LED-Freshwater-Bright-p/56204.htm
There are multiple lengths, and you can spend a bit more and get ones that are supposed to be good enough for reef tanks. Many people have been trying them out and really like them.
The one major thing that I was hoping to get if I went LED was the ability to dim the lights and mimic a sunrise/sunset. Unfortunately, fixtures with that feature are WAY expensive, and the beamswork fixture doesn't do that. I am hoping to maybe modify it to add a controller or something.
