Damn, just ordered a Fly halogen from PW yesterday afternoon. Peter hisself is out on vaca for a couple more weeks and I couldn't get much help from anyone else at the shop, so had to rely on what I could glean from his site and other places I looked. I have a new bike coming together and I was impatient to get something on order.
It's okay, though, I think maybe if you're new to dyno lights it's good to start with halogen just for perspective. I ended up doing way more research than I wanted to and got into some stuff that was written when people were just discovering halogens and what a huge revolution that was. And they have been the shit for a long time.
As I've checked all this out, what has amazed me is how much science is behind how to make the most use of the light that is generated on the dyno side (which makes sense, because if you'er generating the power yourself, you're going to be mindful about how you use it, right?) As you mentioned, most of the modern battery stuff just seems to be all about how to get more light and just throw it out there. What has made the dyno light decision so difficult is the array of beam patterns. In the end, there is only so much that reading about it can do for you, so I just picked one that made sense and decided to start there.
Thanks for the feedback. I might still take you up on the offer to try the E6, as it ovbviously has the reputation and I would be interested to see what it is like. Definitely looking forward to trying dyno hub lighting.