Wow. Me too. Just got mine from Amazon yesterday and took it for a ride last night. It's replacing my 8 year old Light&Motion HID light which has (had?) a similar lumen rating. It's 2/3 the size and less than 1/4 the weight of just the NiMH battery for the old HID light, which was something like $350 at the the time. And it's significantly brighter and with a fairly wide uniform beam. I used to like the HID light because it was fairly hot in the center and had wide low level illumination. Even though the Expilion is brighter in the middle than the HID light, if I could shape the beam I would sacrifice some of the side intensity and make the center even brighter.

That was with the light on the bars. I want to try it mounted to my helmet and see how well that works.

It has 5 steady modes. Walking, which is really very feeble, then Med, High, Boost, and low, in that order. The difference going between Med and High and High and Boost isn't that much visually, but according to the spex has a rather dramatic effect on run times. Low is pretty dim, maybe OK for riding very slowly or in well lit areas. I have not yet verified the run times.

So far, the only place I have found spare batteries for it is the Cygolite website.