This is why I try not to buy many disks at once, just buy one at a time, and if I need more than one I'll go to different stores. Too much chance of getting a b

This is why I try not to buy many disks at once, just buy one at a time, and if I need more than one I'll go to different stores. Too much chance of getting a bad batch of disks and having the whole array go down (I've had that happen too). Of course, that doesn't work at a large scale, but then you have other methods of increasing redundancy.