A few years ago when I built my first rando bike, I agonized over the choices and decided on a Shimano dynohub with a CYO headlight and dyno-powered taillight. For 2 SR series, PBP, and two 24-hour races it has been great - particularly not having any concern about battery life, changing batteries, or charging batteries.
I told myself I'd reconsider when it came time, and it's time. My new rando bike has a different wheelsize, so I'm at least re-lacing a new wheel. I'm sure there are better options this time around. Truth be told, I'd prefer all my watts be propelling me down the road.
Since this will be used for multiple nights of riding with no chance for recharging; runtime is a huge factor. Conditions will vary from urban to rural, riding all night long. I do typically have a small helmet-mount light to help read streetsigns and look around curves.
What kind of run-times are possible these days on a "see with" light in full-on mode?