I bought a cateye HL-EL500 and I received it yesterday. I went out on my ride, and I have to say I am very disappointed. I think LED lights have a way to go before they are viable stand-alone solutions. It's not great for seeing the road, and it definitely is bad for being seen given the focus.

After this I have half a mind to up and buy a 30W MR16 HID...
I'm not kidding.