Why, ? justify..
are you off road 24 hr endurance racing or you just want to blind oncoming drivers, for vengeance ?

http://www.amazon.com/NiteRider-PRO-.../dp/B008L5GB04

$590

Rather than gettin one really bright light, consider getting two moderately bright lights, like two Expilion 700s. You can run both for 1400 lumens, run one steady and the other flashing, one on high and the other off or low then switch to effectively double the run time, aim them differently, put one on the bars and one on the helmet, etc....plus you have redundancy.

I'm a Hub dynamo wired light guy, Myself , Schmidt Hub And Edelux headlight.
mounted at fork crown Height,
and a B&M 4D toplight on the rear rack.

it lights my way on unlit roads in Any weather, as long as I am moving,
and due to a couple capacitors, a while after I have stopped, too..

Any love for the Niteye B20 out there?

There's a nice review of it over on CandlePowerForums.

I've also been eyeing up the Klarus Bk20.

I see both around for $160ish, give or take.

I'd really like to go with Dinotte again (bought the 400R last spring, quite happy), but I just can't do $350.

Pretty sure I'm gonna do the B20 this spring.

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.