And the winner is: Verbatim! Yeah!
Recently bought two 10-packs of Verbatim DLs at OfficeMax.
The first pack is fine.
The second pack has nothing but single-layer disks!
And for a surreal touch, it’s half -R and half +R!
Both packages looked exactly the same and were properly shrinkwrapped in a way that didn’t give any indication of a fraudulent media switch. There also weren’t any fingerprints or dust that would indicate they had been lifted from another spindle.
Let this be a warning, inspect your 10-packs before leaving the store! :o