the firewire charger should be fine.... the current will be slightly higher than a computer's USB port, but the iPod, nanos included (I duno about shuffles), are designed to take an electrical input from 5-30 volts and a maximum of 1 amp, which the firewire charger stays well within. :)... also, the nano should be fine for 1000 songs ripped at 128 kbps AAC.... good luck!
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