Quote from: vinaha on August 24, 2017, 05:10:01 PM

If I have original Casascius coins, will it be possible to redeem them years from now

Yes. As long as Bitcoin continues to exist and have value, it would be possible to redeem them.

Quote from: vinaha on August 24, 2017, 05:10:01 PM

or will the private address at some point become incompatible with the blockchain?

No. That's not how bitcoin works. It cannot become incompatible with the blockchain.

In case you weren't aware...

That Casascius coin has BOTH Bitcoin value AND Bitcoin Cash value. It can be redeemed for either or both.

(Assuming that the Casascius coin hasn't been compromised and had its private key leaked/stolen.)