I long ago gave up on pricey bike lights. I'm currently using a very bright 2 bulb CREE light from China for $35.00. Advertized at 5000 lumen (which is BS) it's the brightest I've ever had, and seems to hold up well (so far), but which I can afford to replace anytime. No investment is a good thing, because every year the lights get brighter, draw less juice, and cost less, so it's nice to be "without a contract".

My backup lights are stock Duracell flashlights that put out 300+ lumens (legit) with a nicely focused beam. Cost is $20.00/set of 3 at Costco. They use 4 AAA batteries. The problem is that they're brighter on alkaline batteries than the lower voltage NiMH, so not my 1st choice. I mount these with Velcro "Bike Blocks" from TwoFish.