Definately the iAudio. Unless you want your player the die in a year I suggest you get the iAudio.
Okay one of the main reasons i want a hard-drive mp3 player is for my car cause i am sick of the radio and to keep having to load cds in...so i have quite a bit of music i would like to listen too, If anyone knows does the cowon iaudi x5 offer some sort of connectivity for there player, like an FM transmiter and if they do how well does it work, and also do i have to have a specific car deck for that player?(mine is just stock, because apple ipod offers a fm transmiter for the car,(not the best) but gets the job done so far that i have listened to one. is this mainly the only reason i want a hard drive player aslo the portablity reason is nice too. help if you can

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