12 years ago I bought a bunch of silver when the spot was about $13 and I opted for a monster box (500) of Canadian Silver Maples instead of American Silver Eagles.
The Maples were 85¢ per oz cheaper than the Eagles ($14 vs $14.85 - ie 6%), and the Maples are a trusted mint and slightly higher purity (.9999 vs .999) so I thought I was making a smart deal.
Turns out, if I sold them now I would get that same 6% less than the Eagles get. If you go on eBay Buy it Now, a monster box of Eagles (500) goes for $17,500 vs $16,500 for the monster box of Maples. That’s almost the same exact 6% discount.
So I figure it all comes out in the wash. If I had spent the same amount of $$ for 6% fewer Eagles, they would be worth what my Maples are worth, so I would have come out the same either way.
I imagine the same is true if you get these non-government rounds, you can get the same amount of silver for a much better price - but then you’d get less for them when you sold them too.
IOW, just like with the Maples, but a more extreme discount.
The point is, there is always a market for pure silver - but it is discounted depending what form it’s in and how much trouble an assayer has to go to to verify its weight and purity.
Determining the weight and purity of silver is an easy technology, so there will always be a market.
Silver eagles are the coin of the realm.
Metals and coin are not the best investment, however, a hundred years from now when silver bars are ,$100 silver eagles will be much more because of the date and condition of the coin.
You are absolutely correct in the way that the premiums work for silver coins in today’s economy. If it ever truly comes down to barter, I suspect the spread will be less for recognized mints, like the US, UK, and CA. There probably will still be some spread between rounds and actual mint coins.
As long as you’re fine with that, buy what makes sense to you. I kinda like having a bit of everything, but prefer larger mints, mainly because they are more widely recognized, and well known.