v8juice, my card is a Samsung Model: MB-MP32D, Model code: MB-MP32DAE/WMT. On package it is marked as UHS-1 and Class 10.
SouthernPhantom, My P3S says invalid card when I attempt to format in units. Your Costco cards, are the SDXC or SDHC?
Mandalay, glad yours are working for you. So maybe my...