@deank , thanks for the reply.
So you are saying that it's recommended to use drives from different vendors, than from the same vendor (brand)? If yes, that would be cool. And with different HDD brands, that's when the Reset USB Bus feature kicks in? I do recall having the USB thumb drive connected when I saw that message from multiMAN. And I did not see that message when I only had the two identical (brand) HDDs connected.When you use drives with different vendor/device IDs mM is able to disconnect both drives and then reconnect them in the proper order.
But then the issue is with the same vendor/device ID HDDs, it will not know which drive to initialize, right? I think I get it now. I will try to get myself a different USB HDD from another vendor. Hopefully that works. Because of what @BahumatLord reports that he is able to have two HDDs connected and both work fine without having to disconnect any of them.The issue is that the PS3 won't play backups from the SECOND drive initialized. On startup it always initializes the right-most port.