Personally, I recommend USB hard disks instead of USB flash disks, because of the performance.SanDisk has yet to fail for me. Just remember to remove the U3-Crap.
Sony MicroVault also worked fine for me (before my dog ate it)
Almost impossible for most consoles, unless your console has a date code.3. quick question: where can i find the DOB of my ps2?
Otherwise, you're left with guessing.