Ive been using the Shimano disc dynohub for 3 winters with a Lumotec Fly LED lamp. It is bright enough for any riding and outshines many battery lamps. In winter I usually ride 1 hr /day with the light on and sometimes more. I really like the grab and go ness with no battery management issues. Also when you lock the bike up there are no bits to remove. Most of my battery lamps have broken due to dropping. If you want to use an additional battery lamp go ahead, its useful for repairs as well.
The dynohub is far superior to other kinds of dynamo for regular use. My touring bike has a bottle dynamo but I dont use it much.