Three weeks ago I sent the FAA two bucks and now I have my new super
cool centennial certificate.

For whoever asked about them earlier, there is a strip on the back like
on credit cards for the airman's signature.

Here's my dilemma: I want to keep it but I will be taking more checkrides.
Say I take the commercial next year but instead of giving up my centennial
card, I hand in my old paper certificate. Will some Okie eagle eye spot
this and bust me, or can I keep the Wright Bros. one forever that way?