Rust is for the pin before a real problem.
When, however, try rum me is something interesting noticed.
The pin has no effect on smooth surfaces and works the better the rougher the surface.
There are advantages and (depending on use) and disadvantages.
Even a couple of points where I have tried:
Rust on metal> Stainless thereafter
Approximately 10 years old firing away on NEN classical electric stove> penetration, paint completely intact
Old yellowed wood> wood like new but efficient material removal. Had to just 30 seconds ne gathered splashing around and who has erased long enough a hole in the wood.
By age and smoking yellowed Kunsttoff> Looks like new without visible scratches in the material.
All in all, ne clear Kaufentfehlung in my view although you should only try it carefully whether to clean and as desired responsive material to be removed on the Glasradierer.
