I've been curious about these, also. Time to replace my incandescent "tractor light" after breaking my second one in a crash. They worked okay for me, but I need something smaller I can mount in a more protected location.
I find the stock Gen2 headlights more than adequate and don't really see how any kind of small LED driving lights could improve upon them, but I like to have a backup if they ever fail. Draw isn't much of a concern for me since any additional lights will never be on when the headlights are on.
I'm probably overly paranoid and think the Gen1 bikes were more prone to headlight failures if a quick switch wasn't made from Hi to Lo beam, but with some of the roads I ride when there's no Moon out, if my headlights suddenly went out, I'd most likely wind up off the road and wrapped around a tree dead with coyotes consuming half my remains before they were found when the sun came up and people started looking for me.
I've got a large 30-amp rocker switch directly under my left hand and I can turn on my backup lights in less than a second. I think even some LED's would provide me with enough illumination to recognize the side of the road enough to slow down and limp home at a lower speed.
I've been wondering if these CREE lights had a noticeable improvement in performance over standard LED lights. I've read some reviews and the phrase "they don't throw much light down the road" seems to pop up a lot but I think a lot of folks expect a lot more out of these lights than they get.