I have never used one, as I fond them mostly useless. I think the best iron I ever used was the one from Black Baron what ever the other iron on film company was. Their iron was one that had special shaped nose on it for getting into tight places or fillets, and was Teflon treated I think. The Top Flite trim iron is only useful to cut the cord off so you can use the wire and/or plug on something else!
Type at you later,
Dan McEntee