With regards to headlights usable for touring, I think there are only two options :
– A powerful LED-based headlight which uses standard batteries
I have A BLT Super Doppler which is focussed and which can also be rotated sideways by about 15 degrees. It's great to highlight signs, what comes after a curve, etc. and has both a steady and flashing mode. The Planet Bike Beamer 5 is more convenient (uses 2 AA batteries instead of 3 AAA ones), but not as powerful.
I heard good comments about the Cateye EL-500 but have never seen one live. Some folks with good eyesight ride all night with 2 EL-500.
– A dynohub
The Schmidt or the new Shimano dynohubs offer very good light without much drag. I have used a Schmidt with dual Lumotecs (see Peter White's website
for details) for 3.5 years and it's great. Light output of a single Lumotec is 2-3 times more than what you get from the BLT Super Doppler. And I recently upgraded my headlight with a Schmidt E-6 and let me summarize the upgrade in one word: Wow!
All other options seen on the Commuting forum don't really work for touring. Rechargeables cannot easily be recharged on the road and rechargeable batteries loose power over time. IOW, if you think you'll use your light once per two weeks, it's more than likely it won't work by then.
Taillights and rear end visibility
I think it's a more important factor to consider. After all, if your headlight is too weak, you can slow down, but your taillights must make you visible to cars and trucks driving by at 100 km/h.
The Cateye LD-1000 seems to be a current favourite. It throws light in most directions so it's a great commuting light. However, rear illumination is not the greatest.
For highway illumination, the [url=http://blt-lights.com/rearLedLights.htm]BLT Red Flare DX throws a little more light than the LD-1000, but most importantly it throws a good beam within 15 degrees, so it's more efficient for warning high speed drivers The Ultra Wazoo has similar brightness but cannot be bolted easily.
However, the best one, I find, is the BLT Rear Super Doppler. Since it's basically a red "headlight", it has a very powerful beam on axis. It's the only taillight I can effectively use as a flashlight. There is one problem with the Rear Super Doppler: it mounts well on a seatpost, but not as well behind a rack.