I agree with just buying a cheap light. < $50 these days can get a perfectly good light. I might, maybe, spend up to $150 if I was going to do something like touring where I needed to be able to count on my light far away from support and space and weight was at a premium, but given that my < $50 light that I'm running now is actually quite nice and it's not a burden to also stash a flashlight and a lockblock in my bag on the way to work, the cheapie is all I need. I definitely would not spend $500 on a light.