the thing about them is that they have hard drives, which, if you run with them too much, will dislocate the reader in the HD, skipping, or even damaging the music on there. for example, if you have an ipod, itll stop after fifteen minutes of running. my friends' one lost all his music on it.flash drives dont have any moving parts, so they don't scratch anything. they're also usually more durable, which is another plus for running.
hope that helps!
I have 2 gb of music is it worth it to get a flash player?

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