I would be very surprised to see this coin fetch anything higher than 10BTC.
Nubbins what were you originally asking for it in the goods section? I can't remember.
Incidentally,
If there was a way to make a wager against this selling for 5 BTC or more, I would for surely accept that.
...
Your coin and its rarity is worth 2.5-3.5 BTC tops.
Both series-2 silvers have been sold, for 13.5 BTC each.
And as a further public service announcement, free of charge to the good folks of the Marketplace sub...
This is as good a time as any to remind people how numismatics are priced.
SALE PRICE = (FACE VALUE) + (NUMISMATIC VALUE) + (SELLER'S PREMIUM)
Notice the lack of multiplication symbols; statements such as "2x face" or "10x face" have no meaning and no place in numismatics.
The FACE VALUE for a Casascius coin would be the value of the BTC stored within, plus the spot value of any precious metals.
The NUMISMATIC VALUE is an absolute value based solely on the desirability of the coin. This generally correlates with mintage, age, and condition, but other factors can be at play here as well.
The SELLER'S PREMIUM varies from seller to seller, based on a number of factors including the seller's trustworthiness, care in packaging, supporting documentation or certifications, and other factors.
The biggest point to make here is that with all other things being equal, FACE VALUE and NUMISMATIC VALUE have no bearing on one another.