I bought my heat plate last year and have never needed to use a dimmer. I have brooded a bunch of chicks and they all loved it. Never had a burned baby. I did lower the back legs and raise the front legs for a while and then just watched as they grew and it needed be raised. I will be buying a cover to use in the future. The press and seal stuff works well but it leaves a sticky film on the top that I don't like.
Just curious - when you touch the plate, is it too hot for you to keep your hand on it?
Some have reported that theirs was too hot to keep a hand on; others have said that theirs weren't that hot. So it seems like they may not all be created equal.
Mine was so hot I couldn't keep a hand on it - and I'm not sensitive to heat so I can usually take a lot.