Flash drives are cheap to buy and more useful on a daily basis, but you will not be able to move over any themes, setting preferences,

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or sign-in information during a PS3 backup. You also have to copy over files manually and may find yourself going between your PS3 and PC to offload files multiple times if you decide to move your movies or music collection. Do not forget to back up your PS3 games saves, as they contain all
the blood, sweat, and tears that you probably do not want to have to relive. Neither PS3 backup option you choose will allow you to copy your game downloads, so those will have to be re-added.
After everything is said and done, you can now rest easier knowing that your data is backed up for your Playstation 3.