I have a black cooktop and made the mistake of buying a ceramic cleaner with conditioner. this leaves a film and I can write on it with my fingers. So I clean it then have to use a window cleaner to remove the film. Another problem is DH uses it as a counter top not a good idea. I made vibrant quilt top to caver the top and remind him "do not use".
No one uses the stove but me. so we have no fires.
I love it when it is clean and would never go back to coils.