I checked out lights at PerformanceBike from cheap to low range expensive (up to $300) and I was not impressed with any of them. Actually many of the more expensive models weren't as bright as the quandrant lights I bought.

If you want to go fast at night you'll need something better. Darn it, I can't remember the link but I did a search on "bicycle light pattern comparison" and found a group of mtb'ers who did a very nice real world study with photo examples. It was surprising how many were terrible even at expensive prices and the really good ones were REALLY expensive.

Here are a few links:

http://eddys.com/page.cfm?PageID=493

http://www.peterwhitecycles.com/headlights.asp

http://reviews.mtbr.com/blog/category/lights-shootout/