My new Knog Gator is plenty bright. DH and I did some after-dark cruising up and down my neighborhood streets when I first got it. When I watched him coming up the dark hill, he was definitely visible, but I don't think I would have mistaken him for a motorcycle or pididdle (for those who remember Sniglets, isn't that a one-headlight car?). But I tend to aim the light down low - directing the beam about 10-15 feet in front of the bike, not up at traffic.
But other than that trial run, until we "spring ahead" next week, it's been too light for my commute to make much use of it. However, I did use the 1W blinkie yesterday (didn't commute today - fighting a head cold)...and the Knog blinkie I have to say is pretty nice. Not seizure-inducing like some of those out there.