Older C8 corrector plates/Upgrading older C8 scopes

I was recently looking at an older C8 (1980)and noticed that the
corrector plate (with special coatings) had several small pits in it.

Now I know the history of this scope and it has always been properly
stored and doesn't have a scratch on it elsewhere. Also when I have
looked through it, the images are quite good.

I guess the question I have is did this scope come with these
imperfections in the corrector plate or is this the natural progression
of time?

The only thing the owner mentioned was that years ago he had installed
a ring magnet on the center of the secondary holder to hold a solar
screen in place and that magnet had slowly disintergrated (moisture?)
and had to be removed. There is no sign of rust on any of the metal
components so I seriously doubt high humidity caused any problems that
could have affected the corrector plate.

Take a look at your corrector plate if you have an older C8 and tell me
if you see any imperfections.

Last question, this user has asked me if he would gain much from buying
a new optical tube from Celestron to place on his Ultima mount (with
PEC). What is your opinion of the quality of the new Celestron
offerings (C8) compared to the older (1980) C8 product?
Thanks for whatever advice you may have to offer.

TMT