In my experience there are some low end CatEye lights, so perhaps that is what you are using for comparison? At any rate, it is all relative to your expectations/needs. I used a CatEye LED light for a while around town. It worked fine for that, but when I tried to get home on the bike/ped paths, under the cover of trees and away from city lights, I was almost blind. I almost hit someone walking their dog. Then I abandoned the paths until I got my NiteRyder (rechargeable, bottle-cage battery), which was so bright my friends always thought a car was coming when I turned it on. Now I have my Spanninga dynamo light (sold in the US by Velo Orange-they don't have my model anymore, but I imagine it's comparable), and I love it for it always being there and never needing recharged, but, while brighter than my CatEye, it isn't nearly as bright as my NiteRyder. There are much brighter dynamo lights available. I just haven't splurged on one yet. See Peter White for some comparisons.

There are dynamo-based charging solutions out there. Do some reading before you go that route. While some people find them very handy, most seem to agree that they are mainly useful if you're going to spend days at a time away from a power source. I looked into it for myself and decided that for the foreseeable future I will be better served by a portable battery that can recharge my electronics for a couple of days at a time and be refreshed from a wall outlet. If you want to recharge devices with dynamo, definitely look at a hub. The bottle dynamos have significantly more drag when in use (but then have zero drag when not in use). At this point, hub dynamos have such little drag that the only advantage of using a bottle dynamo is price. Even if you go that route, I would look for a quality bottle dynamo. There are some cheap ones out there, and I've had mixed success with them, but I've heard that there are some quality ones as well: more reliable with less drag and still cheaper than a hub dynamo.