Check the brush before you buy it. Those dollar store brushes sometimes have metal wire in the bristles and that will scratch the coils. A scratched coil coating rusts way faster and then you got a real problem. Also the coil fins bend if you push too hard, so go slow and light.

Put that old one on Craigslist as "vintage," someone will buy it.

That 2005 clip being used as the fake example is honestly kinda cool in a creepy way, lol.