I prefer a coin with the holo AND the private key with it than nothing but a coin.
This pretty much nails a post peel coins desirability. The more of the original that is still available, the better. Coin, holo AND Priv Key. All part of the provenance of the coin.
As we go forward, provenance of coins is going to become vital.
Coins without it will sell for much less.
Why?
We have yet to see a true wave of determined knock offs appear. When they do, custody chains, PGP certs and anything that can provide quality provenance will be incredibly valuable to a coins resell value.
We have already seen premiums getting mauled as a result of BTC's rise. They will get worse without a full/trustworthy history. This can be said for ANY loaded item.
Viz