Have em on my Kimber, like he said, not too bright, not too dim, I like them.
Honeslty I don't know if I would have paid extra for them though, they came with the gun.
Just not sure (for me) they're worth the extra expense.
I know they are supposed to be very helpful in low light shooting situations, but in my mind if it's that dark that I'm going to need glowing sights to shoot effectively, it's probably too dark to see my target anyway.
But like I said, that's just me.