Save for one remark, I really appreciate all of the good suggestions you posted here and I now have enough information to be...dangerous!

Here's a fairly objective review of current, popular bike headlights, with output testing performed in an integrating sphere (real lumens, not wishful thinking of the seller):

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

Narrow beams are more useful for commuters / road bicyclists; wider beams are more useful for mountain bikers. Since this IS mtbr.com, many of the reviewed lights were specifically chosen for mtb use.

http://reviews.mtbr.com/wp-content/u...umen-chart.jpg

Sending in my Cygolite Expillion 700 in for repair. The flimsy USB cover came off. The light is <4 months old.