You are also going to receive less when you go to sell the 90% -- in some circumstances considerably less. Times won't always be good for silver.
Definitely buy silver dimes and quarters becuase silver is silver BUT if and when SHTF those smaller amounts are easier to barter with rather than trying to get a bottle of water for an ASE. Im not saying that SWHTF but since silver is silver, why not be prepared on the off chance
the whole scenario is just silly and paranoid. no one is going to sell you water if it is that scarce.
Yes, ASEs will command a premium over old 90% coins. But let's say you find some Franklin halves or mercury dimes for 0.85*melt. Would you take that or pay retail for Eagles?
My last bullion purchase was several 1 oz bars at $16. For me, any purchase beyond $20 did not contain a sufficient margin of safety. I don't think melt value is a critically important number for an investor. I would rather buy silver at $30 when melt is $28 than to buy silver at $34 when melt is $36. A lower price = better value regardless of what melt is. Anyway, that's the way I invest.