vio765 said:
i have some time. im not in any hurry. in fact, i am not sure i will be needing a light at all. i think i would prolly go with the Exposure Maxx D or maybe the the new cygolite trion.
My suggestion is that you get the brightest light you can afford. That said, you should pay some attention to the beam pattern.
What is important is that your light puts out enough power that you won't override your light. Overriding a light (or overdriving a light if you're on a motorcycle or in a car) is when you're moving at a speed that doesn't allow you to maneuver safely or see hazards quickly enough to avoid them. Frankly, I don't think you should worry much about adjusting so that you can see in the dark off the side. If you're riding with enough light that you can ride quickly, the intensity range of light is probably such that it either requires that your eyes be focused on the darkness and not on where you're going or it requires too much time for eyes to make any adjustment to be of any help at all.
Here, it's dark. Very dark. In Tucson, Pima County, and surrounding areas, there are light laws that severely limit stray light, at night. Lights must direct a certain amount of light down, and the lights must have an intensity low enough to keep light reflected toward the sky to a specific minimum. The laws were enacted to protect the work being done at the many telescopes in the mountains around here. It's dark in the city and out where we are, it's a lot darker. Very dark. I use all the light I can get, and that allows me to ride as fast as I want.
As for what you need, only you can know. Light manufacturers don't always express light output by the same parameters or same units. If you can, try testing some lights at an LBS at night. It's getting to the time of year when that is feasible. I would suggest a helmet mounted light. Part of having a light is being seen, and I like being able to turn my head and look at drivers coming toward or sitting at intersections, so that my light hits their eyes. It makes it less likely that they'll violently renovate my bike or my skeleton.
I've been eyeing the new offerings from Light and Motion, specifically the Seca line. I believe I see, in my future, a Seca 700.