I have a Rent-a-coop one. I just finished a 3rd batch of chicks under it. Honestly, it does feel hot if you touch it. If you move your hand away even a little, though, you don't feel so much heat. Chicks are meant to be under it, not touching it, so they're ok. (They're fuzz sometimes does look...
Unfair, as I have chicks and take lots of pictures of them. This is my son, Chichetta, and Olive. The next most recent picture was a dead roach at my school. It was huge.