My 40GB has no problems with head phones.
Those transmitters work great, unless your in a metro area where you have alot of interference from other radio stations.
i have about 30GB loaded and leave 10 GBs available for downloading images from my camera. Belkin makes a cool little card reader for the iPod.
I recommend the Sony MDR-EX71 earbuds over the iPod earbuds.

LIFE IS SHORT.
DON'T BE A DICK.