How are iPods for recording music, or for me in particular, singing from a lavalier mic?

I certainly get my best musical inspiration while I’m on the move, and since I’m backpacking across the country this summer, I thought I would wear a lavalier connected to a recorder for fast capture.

iPods have two ways of recording: iPod Classic with Rockbox firmware or iPod Nano 4g or 5g with stock firmware. Both offer WAV recording in 16-bit at 44kHz. So the bitrate and sampling rate is not an issue. And in addition there are iPod hardware accessories that have their own recording circuitry, but I’m not asking about those since information on them can already be found.

>>>>> My question is about other aspects of quality: Does anybody out there have either aneCDotal evidence or reference to scientific measurement of various iPod models’ recording properties like dynamic range, SNR, etc?