-
https://www.merlincycles.com/moon-meteor-storm-1300-front-light-95010.html
Not sure how long this will last in reality but it has a good level of incremental reductions in power. I use it for commuting and the light is good, has a remote on off as well if you're arsed about that sort of thing. There's also a 1700lm version on wiggle for under a ton, too.
There's a breakdown of the power modes/run times here: http://www.moon-sports.com/product-page/meteor-storm
I appreciate the offer, but having never done a 'proper' ride in the night I feel like I would benefit from something more powerful.
This is hopefully the first of many as I'm hoping to do some longer distance audaxy style stuff.