The Supernova E3 Pro has one 3-watt LED and they claim it has an efficiency of over 100 lumens per watt, so you can get a little over 300 lumens under good conditions.

The E3 Triple has two more LEDs. According to an older post on this forum, it starts out with just one LED lit and is no brigher than the E3 Pro at low speeds, but at speeds greater than 15 or 20 mph the other LEDs are also powered. A hub dynamo is capable of generating well over 3 watts at high speed (I believe the Schmidt hub dynamo can put out more than 6 watts), so you could get 600 lumens with 6 watts at 25 mph / 40 kph

The Triple is also only available with a round beam, which would tend to blind oncoming traffic if you are on a public road; the E3 Pro also has a shaped beam with a vertical cut off, like car low-beams. Seeing that a car's low beams are about 1000 lumens each, a 300 lumen light should probably have a focused beam to avoid dazzling traffic.

I would think the E3 Pro, or similar lights like the Edelux or the B&M Lumotec IQ Cyo, would be better for use in the city.