I have heard this a lot. My beardie has a ho t5 tube. But for the breeding gecko terrarium I want to use a coil bulb I have. I have some friends who suggest trying it for cresties.
But I heard the old coil bulbs are bad but the new ones are much better. If it's kept at a distance and not angled at them so it's not directed into their eyes is ok. Hoping that's true...