I like the color of copper, but managing cupric oxide would be a potential headache, especially if it flakes off into the electronics (which it is likely to do on a moving part, like buttons).

You could possibly mitigate this somewhat by running the buttons through a polishing tumbler with burnishing media, but it would give me too much stress knowing that even this isn’t 100% effective.

The existing buttons are made out of a plastic that wears well when rubbing against their contact-points in the case. The plastics are chosen to be compatible, self-lubricating and “not spalling or rubbing eachother to death”.

I doubt that these metalized buttons have been tested for their long-term wear characteristics.

As someone who modded his controller with metal buttons. Instant regret. It is not comfortable for extended gaming sessions.

Now you can smell like pennies