They spook from both, just not as much I don't think as the regular flash. I have the No Flash Cuddeback and I've got a few pics of them heading out from the picture when it was getting taken. Its more the noise that scares them on my No Flash then anything I think. When it takes a picture it makes the slightest little noise. I can't hear it but my brother has heard it before when checking the camera.

Here's a picture of one spooking from my No Flash Cuddeback.