I've listened to the pros and cons between both battery and dynamo set-ups till the cows came home and nothing I've read so far can really convince me that one is particularly better than the other.

As I see it someone that prefers a dynamo is usually concerned about having unlimited run time. To me this is it's biggest advantage. However if you typically ride at night no more than three hours a battery set-up is probably the easiest/least expensive way to go.

I've been riding with battery lighting for a good number of years now. When LED/Li-ion set-ups came out I was over-joyed. They are small, light weight and in most cases attach to a bike in less than a couple minutes. I now just leave the lamp head on the bike most of the time unless I plan to leave the bike outdoors unattended for more than a couple minutes.

I've never tried Dynamo lighting. Not because I don't like them but because I'm not convinced that I would be satisfied with the beam pattern/ output level. The lights I use now cost me very little and meet most of my expectations. If I went through the trouble of having a wheel built with a dynamo hub I doubt that I would be able to return the wheel/hub if I ended up not liking the resultant set-up. Dynamo lamp heads are another issue. There are many to choose from and I'm picky about having a lamp that provides a beam pattern that covers the WHOLE road ( from directly in front of the bike to a good distance in front of the bike ). I don't like "dead zones" in the beam pattern.

All that said, I think I'm relatively intelligent enough to find a dynamo system that would work for me but it would involve a lot of shopping around on-line and reading a lot of reviews. If I ever decide to do a road endurance event where I spend more than six hours riding at night than I would prefer a dynamo. Since I'm not into such events I'll likely continue using battery lights because they are less expensive and also work very well. With a good two cell I can even get over 2 hrs run time if I watch how much I use the high beam. Since I ride with lower output levels most of the time anyway this is really not a problem for me.