plastic is seen by some (probably many) as a serious problem. If you intend on having them filled in a way that clearly differentiates them from the originals (like the arty Hard Rock brass cores), then some have no problem with that. Filling them in to look like the originals is somewhat tantamount to counterfeiting in some eyes. Just a warning.

The more chips that are created or repaired to look like the originals, the less we can trust that any chip is genuine and it creates a significant problem with values. You can see why some do not like it.

So, consider what you are doing before you do it. Just trying to be helpful.

Michael Siskin